Abstracted direct fetch calls across components and contexts into new functions within `src/lib/client.ts`. This provides a consistent and centralized interface for interacting with backend APIs.
- Introduced `src/lib/client.ts` to encapsulate API request logic.
- Standardized audio buffer types (`TTSAudioBuffer`, `TTSAudioBytes`) in `src/types/tts.ts`.
- Moved client-specific request types (`TTSRequestPayload`, `TTSRequestHeaders`, `TTSRetryOptions`) to `src/types/client.ts`.
- Updated API routes and consumer components/contexts to leverage the new client library functions and type definitions.
- Removed `src/utils/audio.ts` as its utility functions are now part of `src/lib/client.ts`.
- Removed `onProgress` callback from `regenerateChapter` and related functions across `TTS`, `EPUB`, and `PDF` contexts to simplify the chapter regeneration API.
- Updated `AudiobookExportModal` to align with the refined regeneration API, including removing granular chapter progress display and adding a hint about TTS caching behavior.
- Introduced `TTSAudiobookChapter` interface and renamed `ContinuationMergeResult` to `TTSSmartMergeResult` and `PageTurnEstimate` to `TTSPageTurnEstimate` for better type consistency and clarity.
- Applied minor styling adjustments to buttons and listbox components in modals for visual consistency.
- Added `'use client'` directive to several client-side components for Next.js 13+ compatibility.
- Updated Dockerfile build command from `pnpm run build` to `pnpm build`.
- Added Playwright tests to verify backend chapter state after regeneration.
