Refactor EPUB and HTML word highlighting to use a shared, position-preserving
text normalization pipeline for mapping TTS alignment offsets to DOM positions.
Replace the previous fuzzy token-matching logic with a direct char→DOM map
based on the canonical "audio" text form, ensuring highlights stay in sync
across languages and with Unicode-aware hyphenation handling.
- Add `highlight-char-map.ts` for shared normalization logic
- Update normalization to handle Unicode hyphenation consistently across
compute, client, and shared layers
- Remove unused fuzzy token mapping and cache logic from EPUB highlighting
- Update tests for new highlight mapping and normalization behavior
BREAKING CHANGE: Removes legacy fuzzy token-based word highlight mapping in favor of direct char offset mapping; highlight cache and tokenization APIs are removed.
Consolidate EPUB TTS segment planning around a single canonical windowing model.
Introduce `epub-canonical-window.ts` to provide stable, viewport-independent
segment windows for both playback and sidebar. Refactor segment planning,
prefetching, and playback handoff to use canonical ordinals and keys, ensuring
that segments straddling page breaks are uniquely identified and never replayed
across pages. Update TTSContext, SegmentsSidebar, and related hooks to support
windowed canonical segments and precise ordinal continuity. Extend types and
interfaces to carry canonical segment metadata and windowing context.
Add comprehensive unit tests for canonical window selection, segment
materialization, and cache behavior.
BREAKING CHANGE: EPUB TTS segment planning, playback, and sidebar now rely on
canonical windowing, affecting segment key generation and playback logic.
* refactor(user): overhaul user data cleanup and export for cascading deletes and TTS segment support
Revise user data cleanup logic to ensure proper cascading deletion of user-related
database rows and S3 objects, including shared document and preview artifacts.
Introduce explicit checks for last ownership before removing shared resources.
Add TTS segment cache and audio cleanup to document and user deletion flows.
Expand user data export to include TTS segment entries and audio, job events,
document settings, and linked auth sessions. Update schema with ON DELETE CASCADE
for userTtsChars and userJobEvents. Add new migration scripts and comprehensive
unit tests for cleanup and export scenarios.
* test(user): expand cleanup and export coverage for shared docs and TTS segment files
Add tests for user data cleanup with shared document ownership and for TTS segment
variant export scenarios, including cases with duplicate audio keys and storage
disabled. Refactor cleanup logic to use document row types and transactional
ownership removal with last-owner checks. Update TTS segment cache clearing to
report deleted segment count by unique entry. Adjust export logic to always
include all TTS segment variants and conditionally export file buckets based on
storage availability. Update migration to use NOT VALID/VALIDATE for new
cascading constraints.
* refactor(documents): centralize owned document deletion and add mutation locking
Introduce `deleteOwnedDocument` utility to encapsulate all logic for removing a user's ownership of a document, including TTS segment cache cleanup, preview artifact removal, and S3 blob deletion for last-owner cases. Add `withDocumentMutationLock` to serialize concurrent mutations on the same document, using advisory locks in Postgres and a local queue fallback. Refactor all API routes and user data flows to use these utilities, ensuring transactional safety and preventing race conditions during document deletion or transfer. Update tests for new flows and add coverage for document cleanup sequencing and locking behavior.
* feat(data): enhance anonymous claim to support document settings and TTS segment copy
Expand the anonymous data claim process to include document settings transfer and TTS segment S3 prefix copying. Remove foreign key constraints from user_tts_chars to allow non-user buckets. Update claim modal and onboarding flow to display claimed document settings. Refactor TTS char count transfer to merge all dates and fix upsert logic. Add S3 copy utility for TTS segments and corresponding tests. Update migrations and schema to reflect relaxed constraints.
* refactor(data): improve error handling and rollback for document and TTS segment operations
Enhance robustness of document deletion and TTS segment transfer by improving
error logging, partial rollback, and degraded state reporting. Add best-effort
cleanup and recovery mechanisms to prevent orphaned data and ensure diagnostic
information is captured for unexpected failures. Update user data cleanup to
log and swallow restoration errors without masking primary failures. Refine
claim logic to handle unmapped TTS audio keys safely.
* refactor(data): unify document mutation locking and transaction handling
Replace mutation-lock with document-lock to centralize document mutation
serialization and database transaction management. Introduce runInDbTransaction
utility to abstract SQLite/Postgres transaction differences. Update document
deletion, user data cleanup, and rate limiter logic to delegate transaction
handling and locking to shared helpers. Remove dialect-specific branching and
inline transaction logic for improved maintainability and testability.
BREAKING CHANGE: withDocumentMutationLock is removed in favor of withDocumentLock and runInDbTransaction
* fix(documents): improve rollback error handling in deleteOwnedDocument
Enhance error handling during document deletion by ensuring that failures
in restoring document ownership do not obscure the original error. Log
degraded events when ownership restoration fails after a deletion error,
providing additional context for debugging and monitoring. This change
improves reliability and traceability of document deletion operations.
* feat(tasks): introduce scheduled task engine and admin UI for background jobs
Add a general-purpose scheduled task system with a persistent registry and status tracking, supporting background maintenance jobs such as orphaned blob reaping, expired upload cleanup, job event pruning, and TTS usage retention. Implement a new `scheduled_tasks` table, task engine, and handlers for each maintenance operation. Integrate an admin UI panel for monitoring, manual runs, and configuration of tasks. Update document and user data cleanup flows to delegate shared blob and preview deletion to the scheduled reaper. Add Vercel cron integration for serverless environments.
BREAKING CHANGE: Document and user storage cleanup now relies on background scheduled tasks for shared blob and preview deletion; immediate inline deletion is no longer performed.
* refactor(user): streamline document and TTS segment transfer logic
Simplify user document transfer by consolidating storage and metadata handling. Remove inline deletion of shared blobs; only metadata is moved, and TTS segment transfer is controlled via options. Add `skipStorage` option for test scenarios to bypass storage operations. Update tests to reflect new transfer behavior.
* chore(instrumentation): delegate node-specific setup to separate module
Move Node.js-specific instrumentation logic to a dedicated file. Update
registration to dynamically import the node module only when running in a
Node.js environment. This separation clarifies environment-specific behavior
and improves maintainability.
* ci(config): update scheduled task cron to run daily at midnight
Change cron schedule for /api/admin/tasks/tick from hourly to once daily at
midnight to reduce task frequency and align with updated operational
requirements.
* refactor(tasks): enforce positive interval and improve scheduled task updates
Add database-level check constraints to ensure scheduled task intervals are always
positive for both Postgres and SQLite. Update admin API and UI to support sub-minute
intervals and stricter validation. Refactor scheduled task update logic to upsert
rows, ensuring tasks can be updated even if not yet present in the database.
Improve temporary upload cleanup to delete in paginated batches. Enhance tests to
cover new constraints and update behaviors.
* chore(docker): remove ffmpeg-static from runtime dependencies in image build
Eliminate ffmpeg-static from the production node_modules during Docker image
assembly to streamline the deployment artifact and avoid bundling unused binaries.
* refactor(admin): redesign task panel UI with Card layout and running indicator
Replace the bordered div layout in AdminTasksPanel with the Card component for
improved visual hierarchy. Add a dynamic running indicator using a custom
RunningDot component to clearly show active tasks. Update control alignment and
button states for better usability. Remove Badge-based status display in favor
of a more streamlined appearance.
* feat(tasks): add document blob lease for safe orphan reaping and improve scheduled task robustness
Introduce a document blob lease mechanism to prevent race conditions between document registration and orphaned blob cleanup. The new `document_blob_leases` table ensures that only one process can claim a document blob for mutation or deletion at a time. Update the orphan reaper to acquire a lease before deleting blobs and to re-check for ownership after acquiring the lease, avoiding accidental deletion of in-flight uploads.
Enhance scheduled task infrastructure with per-task fencing tokens to prevent stale runners from overwriting newer results, enforce runtime limits with abort signals, and expose scheduler mode and minimum interval to the admin panel and API. Adjust task handlers to accept a context with abort support, and update documentation and environment variable references for the new cron secret and scheduling behavior.
BREAKING CHANGE: Scheduled tasks now require a `document_blob_leases` table and updated handler signatures. Vercel deployments must set `CRON_SECRET` for scheduled maintenance.
* refactor(admin): add loading skeleton to tasks panel for improved UX
Introduce a TasksSkeleton component to display animated placeholders while scheduled tasks are loading. Replace direct rendering of empty task rows with the skeleton when data is pending, enhancing perceived responsiveness and user experience in the admin tasks panel.
* test: clean up playwright anonymous users
* test: make blob lease expiry deterministic
* fix(documents): improve blob lease release error handling and test stale lease scenario
Handle errors during blob lease release by logging warnings instead of allowing them to mask original results. Update unit tests to verify that releasing a stale lease does not affect a replacement lease.
* refactor(documents): implement exponential backoff with jitter for blob lease retries
Replace fixed retry delay with capped exponential backoff and jitter to reduce
contention and thundering herd effect when acquiring document blob leases. This
improves lease acquisition fairness and efficiency under high load.
Update preference normalization logic to explicitly reject arrays when
validating record types, ensuring only plain objects are accepted. Adjust
ConfigProvider effect conditions for clarity and correctness. Add unit tests
verifying that arrays are not accepted as valid preference records or saved
voices.
Move provider normalization logic into a dedicated module to ensure consistent
handling of provider defaults and user preference inheritance across client and
server. Update layout components to mount ConfigProvider only at the shared
layout level, preventing unnecessary remounts and hydration issues during
navigation. Adjust app config defaults so user provider settings are empty by
default, always inheriting the admin-configured provider unless explicitly set.
Add tests for normalization and sync logic to ensure robust provider resolution.
Remove the separate docx-to-pdf upload API and integrate DOCX conversion directly into the blob upload finalize route. Update client and uploader logic to treat DOCX as a supported upload type and streamline batch state handling. Adjust document caching and test helpers to align with the new unified flow. Add server-side DOCX-to-PDF conversion utility and corresponding unit tests.
This change simplifies the upload pipeline, consolidates conversion logic, and improves maintainability.
Replace type-specific document add/remove functions with generalized uploadDocuments and deleteDocument methods. Consolidate file upload handling in DocumentUploader for improved maintainability. Introduce evictCachedDocument to streamline cache eviction across document types. Update DocumentContext to support batch uploads and single-method deletion, simplifying context API and reducing duplication.
Add PDF_PARSER_VERSION constant and propagate parser versioning throughout
the PDF parsing, job, and API layers. Implement normalization of parse state
to ensure compatibility with the current parser version, and enable reuse of
parsed PDF results when possible. Add isPlaybackReady state to document hooks
and TTS player, improving playback UX by disabling controls until content is
ready. Update tests to reflect new playback readiness logic.
BREAKING CHANGE: PDF parse state and job logic now require explicit parserVersion;
older parse states may be treated as pending until reprocessed.
Eliminate the enableDestructiveDeleteActions feature flag from runtime
configuration, admin panel, environment docs, and user settings modal.
Remove all references, toggles, and documentation for this flag. This
simplifies the runtime config and user interface by consolidating
destructive actions under account deletion only.
BREAKING CHANGE: The enableDestructiveDeleteActions runtime flag is no longer supported. Any configuration or code depending on this flag must be updated.
Eliminate the unused authEnabled property from context providers, hooks,
components, and API responses. All logic and UI now assume authentication is
required, simplifying prop signatures and reducing branching. Update related
types, context values, and function calls to reflect this change. This streamlines
the authentication flow and removes unnecessary configuration.
Eliminate all code, tests, and utilities related to the legacy 'unclaimed' user
scope. All API endpoints, document and audiobook storage, and access logic now
require a valid authenticated userId and only operate on resources owned by that
user. Remove related helper functions, test cases, and conditional flows for
anonymous/unclaimed data. Update types, client APIs, and UI logic to reflect
that only 'user' scope is supported. This simplifies ownership checks and
removes ambiguity around document and audiobook access.
Eliminate all code paths, configuration, and documentation related to running
without authentication. Require AUTH_SECRET and BASE_URL at startup, updating
middleware, server logic, and runtime checks to assume auth is always enabled.
Simplify onboarding, settings, and test helpers to reflect mandatory auth.
Update environment examples, Docker and deployment docs, and CI/test configs.
Remove no-auth-specific UI flows, test cases, and feature toggles.
Remove TTS cache and upstream tuning environment variables in favor of admin-managed
runtime settings. Add new admin panel controls for TTS retry attempts, upstream timeout,
audio cache size, and cache TTL. Update API routes and TTS generation logic to consume
these runtime-configurable values, enabling live adjustment without redeploy. Update
documentation to reflect the removal of related env vars and the new admin workflow.
- Remove legacy TTS rate limit environment variables and migrate all related configuration to runtime settings managed via the Admin UI
- Add runtime config keys for TTS rate limiting enable/disable and per-user/IP daily quotas
- Refactor rate limiter and API routes to use runtime config for thresholds and enablement
- Update AdminFeaturesPanel to allow editing TTS rate limiting and quota values in the UI
- Add shared-provider-selection utility for consistent provider selection logic
- Update documentation to reflect new runtime/admin configuration and remove obsolete env var docs
- Add unit tests for rate limit runtime settings and provider selection
BREAKING CHANGE: TTS rate limiting is now controlled via Admin → Site features; environment variables for TTS rate limiting are no longer supported and will be ignored.
Extract onboarding flow step resolution and async runner logic into a
dedicated module for better separation of concerns and maintainability.
Refactor context/provider to use new helpers and simplify settings modal
control. Add unit tests for onboarding step resolution and async runner
coalescing. Update e2e helpers and selectors for onboarding modals.
Adjust environment file handling for CI and Docker contexts.
- Add .dockerignore for build hygiene
- Refactor onboarding context and modal logic
- Add src/lib/client/onboarding-flow.ts with core onboarding helpers
- Add onboarding-flow unit tests
- Update Playwright config and scripts for CI env loading
- Improve test selectors for claim modal
- Update .gitignore to exclude all .env* except .env.example
This change increases onboarding logic modularity and reliability, and improves CI/test environment handling.
Update TTS context to include configProviderType, supportsInstructions, and
ttsInstructions in the provided value, improving downstream access to provider
capabilities and instruction handling.
Introduce clearSegmentCaches to TTS context for explicit cache invalidation after segment clearing. Enhance SegmentsSidebar scroll logic to better distinguish user-initiated and programmatic scrolls, improving UX during segment updates.
Eliminate the smartSentenceSplitting configuration flag from application state, UI, and all TTS and audiobook adapter logic. Consolidate TTS segment planning to always include context units, streamlining code and reducing conditional branches. Update tests and type definitions to reflect the removal of this feature toggle.
Update TTS segment prefetching logic to handle arrays of CanonicalTtsSourceUnit for upcoming and next locations, enabling more precise TTS segment mapping. Expand cache key construction to include providerType and instructions, improving cache differentiation for TTS requests. Adjust related types and usages to support richer segment metadata propagation.
- Replace `OPENREADER_COMPUTE_MODE` and related variables with `COMPUTE_MODE`
- Replace `OPENREADER_*` PDF/Whisper model URLs with `PDF_LAYOUT_MODEL_BASE_URL` and `WHISPER_MODEL_BASE_URL`
- Remove legacy `NEXT_PUBLIC_*` runtime config seeds in favor of `RUNTIME_SEED_*`
- Update documentation, code, and environment references to match new variable names
- Remove deprecated `scripts/fetch-models.mjs` and related npm script
- Update runtime config SSR injection from `window.__OPENREADER_RUNTIME_CONFIG__` to `window.__RUNTIME_CONFIG__`
- Adjust Next.js config to use new compute mode env var and optimize output file tracing for ONNX dependencies
BREAKING CHANGE: Environment variable names for compute mode, model URLs, and runtime config seeding have changed. Update `.env` files and deployment configs to use `COMPUTE_MODE`, `PDF_LAYOUT_MODEL_BASE_URL`, `WHISPER_MODEL_BASE_URL`, and `RUNTIME_SEED_*` as appropriate. Legacy `OPENREADER_*` and `NEXT_PUBLIC_*` variables are no longer supported.
Migrate PDF parsing to use ONNX Docling layout model for structured block extraction, enabling improved TTS segmentation and chaptering. Add compute backend abstraction for heavy tasks (alignment, layout parsing) with configuration via `OPENREADER_COMPUTE_MODE`. Integrate block-level locators and document settings for per-document PDF parsing options. Update S3 storage for parsed PDF JSON, add migration and schema changes, and extend client and server APIs for parsed data and settings. Remove legacy word highlight flag in favor of compute capability detection.
- Add ONNX model download, local/none compute modes, and `onnxruntime-node` dependency
- Update PDF viewer and TTS pipeline to use parsed blocks and block-level locators
- Add document settings storage and APIs for per-document PDF options
- Update S3 storage layout for parsed PDF JSON
- Add admin/config/docs updates for new compute and parsing features
- Remove obsolete word highlight runtime flag and UI
BREAKING CHANGE: PDF parsing and word highlighting now require `OPENREADER_COMPUTE_MODE=local` and ONNX model; document settings and S3 layout updated; legacy word highlight flag removed.
Introduce sentence and word highlighting for HTML/TXT/MD documents, including new config options (`htmlHighlightEnabled`, `htmlWordHighlightEnabled`) and synced user preferences. Update the HTML viewer to support these highlights using custom spans, and add corresponding CSS styles. Extend document settings to allow toggling these features. Implement block-level locator sorting and display improvements. Add audiobook export support for HTML documents, including adapter and pipeline integration.
- Add `htmlHighlightEnabled` and `htmlWordHighlightEnabled` to config, user state, and Dexie storage
- Update HTML viewer to apply and manage highlights for sentences and words
- Add CSS for HTML highlight classes and scroll margin
- Extend document settings UI for HTML highlight toggles
- Support HTML audiobook export in modal and pipeline
- Improve block locator sorting and sidebar display for HTML
- Add HTML audiobook adapter and block parsing utilities
Introduce `enableUserSignups` runtime setting to allow administrators to control
whether new accounts can be created. Update environment variable and documentation
references to support this feature. UI elements for account creation are now
conditionally rendered based on this flag. Signup attempts are blocked server-side
when disabled, including email, OAuth, and anonymous upgrades.
Add `assertUserSignupAllowed` utility for consistent enforcement and corresponding
unit tests to verify policy behavior.
Introduce changelog feed manifest support, including client and shared
utilities for fetching and parsing changelog data. Add a new
Settings modal panel for viewing changelog entries, with version
detection based on the current app version. Expose a configurable
changelog feed URL in both environment variables and admin panel
runtime settings. Update documentation and deployment workflow to
support changelog feed generation and consumption. Include unit tests
for changelog utilities.
Eliminate the showAllDeepInfraModels runtime/admin config and all code paths
that allowed restricting Deepinfra's model catalog. Deepinfra now always
shows the full model list regardless of API key or environment variable.
Update documentation, environment examples, admin panels, runtime config,
provider catalog logic, and tests to reflect this change.
Adopt @tanstack/react-query for data fetching and cache management in admin
settings, provider management, shared provider hooks, and context providers.
Replace legacy useState/useEffect data loading with react-query's useQuery and
useMutation patterns. Refactor document, rate-limit, and shared provider
contexts to use query keys and cache invalidation for consistent state across
the app. Add QueryClientProvider to root providers. Update package.json to
include react-query dependency.
Remove fallbackProviderRef usage from settings and config context to streamline
provider resolution. Adjust normalizeLegacyProviderRef to retain 'default-openai'
unless a non-default fallback is explicitly provided. Update provider listing to
enforce deterministic ordering by updatedAt, createdAt, and slug. Expand unit tests
to verify provider ordering, legacy ref normalization, and selection logic.
Transition all TTS-related logic, types, and UI to use the new providerRef/providerType model in place of legacy ttsProvider fields. Introduce a centralized tts-provider-policy module to encapsulate provider/model capability checks, default value resolution, and compatibility logic. Update all API routes, contexts, hooks, components, and tests to use providerRef and providerType, ensuring consistent handling of built-in and shared TTS providers. Remove legacy defaultTtsModel config in favor of per-provider defaults and shared provider admin control. Add the showAllProviderModels runtime flag to restrict users to provider default models when desired.
BREAKING CHANGE: ttsProvider fields are replaced by providerRef/providerType throughout the codebase; defaultTtsModel config is removed in favor of per-provider defaults.
Add database-backed runtime configuration for feature flags and TTS provider credentials, editable via a new admin UI panel. Replace static NEXT_PUBLIC_* and TTS provider env vars with admin-managed settings stored in the database and injected at SSR for client access. Implement admin-only panels for managing shared TTS provider credentials (with encrypted API keys) and live site feature flags. Add schema migrations, API routes, React contexts, and hooks for SSR-injected runtime config and live updates. Update client and server logic to resolve configuration from the database at runtime, enforcing admin restrictions and supporting migration from legacy env-based config.
BREAKING CHANGE: Feature flags and TTS provider credentials are now managed at runtime via the admin UI. Environment variables are only used for initial seeding and are ignored after first boot. Existing deployments must migrate configuration to the admin panel.
Move `epub-word-highlight`, `tts-epub-handoff`, and `tts-epub-preload` from shared to client/epub to clarify their usage and improve bundling. Update all imports to use new client paths. Extend TTS and sidebar logic to support HTML document progress tracking and restoration, introducing a new location format for HTML and consistent handling for non-EPUB readers.
BREAKING CHANGE: EPUB TTS utilities relocated to `lib/client/epub`; update import paths. HTML progress persistence now uses a new format incompatible with previous versions.
Redesign TTS segment storage by decomposing the `tts_segments` table into two normalized tables: `tts_segment_entries` for unique segment identity and locator projection, and `tts_segment_variants` for per-settings audio variants. Update schema, queries, and API routes to use the new structure, including manifest pagination and segment resolution logic. Refactor segment locator handling to use stable projections and manifest cursors. Migrate tests and data cleanup utilities to support the new model.
BREAKING CHANGE: Database schema for TTS segments is now split into entry and variant tables; all code and consumers must use the new structure. Persisted data and APIs relying on the old `tts_segments` table are incompatible.
Implement strict validation for EPUB TTS segment locators, requiring stable spine coordinates (`spineHref`, `spineIndex`, `charOffset`) and rejecting legacy CFI-only locators. Introduce `segmentKey` as a normalized identity derived from segment text, used for robust merging and deduplication of synthesized and persisted segments. Update database schemas, API routes, and manifest logic to support the new locator format and segmentKey. Add helpers for locator resolution and segmentKey construction, with comprehensive unit tests for identity, normalization, and manifest grouping.
BREAKING CHANGE: Persisted EPUB TTS segment locators must now include stable spine coordinates; legacy CFI-only locators are no longer accepted. Consumers must handle the new `segmentKey` field for segment identity and merging.
Refactor TTS segment identification to support canonical segment keys, decoupling segment IDs from locator and index for more robust deduplication and handoff. Add `segmentKey` to segment types, manifest, and ensure route. Implement natural sorting for EPUB CFI locations and segment locators using new comparison utilities. Update sidebar and manifest helpers to use locator-aware sorting. Add foundational modules for EPUB word highlighting, TTS segment planning, and EPUB handoff logic. Expand types and tests to cover new canonical segment and locator behaviors.
BREAKING CHANGE: TTS segment IDs now support canonical segment keys; APIs and manifest consumers must handle `segmentKey` and updated locator comparison logic.
Introduce configurable segment preloading depth, sentence lookahead, and TTS segment max block length for both PDF and EPUB readers. Add new settings to user preferences, config context, and document settings UI. Refactor TTS segment splitting logic to support per-user max block length and propagate these options through PDF/EPUB adapters and TTS segment generation. Update API, manifest pagination, and segment deduplication for improved performance and correctness. Add tests for new NLP options and manifest logic.
BREAKING CHANGE: TTS segment splitting and manifest APIs now require max block length and preloading parameters; user config schema updated.
Introduce logic to provide previous text context for TTS sentence splitting,
enabling more accurate prefix stripping and improved handling of segment
boundaries. EPUB and PDF providers now supply previous segment text, and
TTSContext leverages this context to avoid redundant continuation logic.
This enhances TTS playback continuity and reduces repeated or truncated
sentences across segment transitions.
Update TTSContext to track manual pause epochs, ensuring explicit user
pauses are respected during async sentence splitting and playback state
restoration. Adjust TTSPlayer button disabling logic to allow pausing
while processing. Move and improve pauseTTSAndVerify helper for robust
cross-browser TTS pause assertions, replacing local test implementations.
Update expectDocumentListed to use polling for document link visibility.
Introduce SegmentsSidebar component and supporting reader UI for segment-level
navigation and inspection. Add TTS segments manifest and clear API endpoints to
enable efficient retrieval and management of segment variants. Update TTS
segment schema to include settings_hash for improved lookup and indexing,
and adjust indexes to use settings_hash instead of settings_json. Update
contexts and types to support segment variant display and interaction.
This enhances document navigation and TTS segment management for end users.
Introduce `playbackRunIdRef` and `invalidatePlaybackRun` to ensure that playback
state is correctly reset on abort and content changes. Update abort and navigation
handlers to call `invalidatePlaybackRun`, preventing duplicate or stale playback
runs, especially in scenarios with rapid restarts or browser-specific audio event
quirks. This addresses issues where playback could become stuck or behave
unexpectedly due to outdated in-flight guards.
Remove legacy TTS segment manifest and audio endpoints in favor of new presigned and fallback audio URL approach. Update segment manifest structure to include `audioPresignUrl` and `audioFallbackUrl` fields, deprecating the previous `audioUrl`. Refactor segment ensure logic and TTS context to utilize the new playback source model. Add server utilities for generating presigned S3 URLs and introduce new API routes for presign and fallback audio retrieval. Clean up obsolete client API functions and types to reflect the new manifest format.
