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 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.
Refactor chapter API to use new coerceAudiobookGenerationSettings utility for
validating and migrating audiobook metadata. Add src/lib/server/audiobooks/settings.ts
with shared logic and introduce corresponding unit tests to ensure correct
settings migration and validation.
