Replicate TTS provider, improved pause, pin SeaweedFS

Add persistent custom theme with live color editing and configurable …

…TTS upstream timeout.

Refactor TTS and audiobook pipelines, harden voice/config and abort h…

…andling, stabilize UI/export tests, plus SQL migration fix.

Move audiobook generation more server-side, new settings looks, and f…

…ixes

Officially support KittenTTS-FastAPI

Auth, sql-db, s3-like storage; major overhaul

Enhanced NLP and PDF highlighting for bug fixes and improvements

 External library imports, document selection modal, and file system …

…upgrades with migration logic

File previews in grid layout + upgrade React/Next for CVEs

Bug fixes