improve container startup for rootless Podman, plus related refactors and tests. Key changes:
- Add/modify Audiobookshelf-related code and wiring (src/lib/services/audiobookshelf/api.ts, library service refs) and update documentation TABLEOFCONTENTS to reference ABS implementation.
- Detect user namespace in docker/unified app-start.sh and redis-start.sh and skip gosu when running in rootless Podman to preserve UID mapping; improve startup logging and verification.
- Add utility/service files (auth-token-cache.service.ts, credential-migration.service.ts, cleanup-helpers.ts) and corresponding tests; update chapter-merger and metadata-tagger utilities/tests.
- Update many admin/auth API routes and tests to reflect changes in settings and integrations.
- Remove large AI agent and Audiobookshelf implementation guide docs (AGENTS.md and the implementation guide) and add README note about AI-assisted workflow.
These changes enable Audiobookshelf backend mode, improve compatibility with rootless container runtimes, and include cleanup/refactor work and unit tests.
Fix PUID/PGID collision issues by using gosu to run services with exact UID:GID. Changes include:
- Added redis-start.sh and updated app-start.sh to load /etc/environment, determine PUID/PGID, and invoke gosu "$PUID:$PGID" to start Redis and the Next.js app (with verification and fallbacks).
- Updated entrypoint.sh to persist PUID/PGID into /etc/environment, document the gosu approach, and adjust startup messaging.
- Updated supervisord.conf to run the new startup wrappers as root (so they can use gosu) instead of running processes directly as specific users.
- Dockerfile updated to install gosu and copy the redis-start.sh wrapper.
- Documentation updated (deployment/unified.md) describing the PUID collision bug, the root cause, and the gosu-based fix.
This resolves cases where PUID collides with existing system users (e.g., nobody) which previously caused processes to run with the wrong GID and produce EACCES errors.
kikootwo