fix: Ensure essential data files are preserved in Docker containers
- Modify entrypoint.sh to preserve built-in data files in /app/data
- Add selective volume mounting in docker-compose.dev.yml
- Prevent mkdir from overwriting image's data directory contents
- Add logging to verify essential files (quotes.json, awards_mapping.json, anime-offline-database-minified.json)
- Mount only runtime data (aphrodite.db, scheduler/, backups/) while preserving static reference files
- Update .dockerignore with explicit inclusion rules for JSON data files
Fixes issue where Docker containers were missing essential reference data files
that are required for quotes, awards mapping, and anime database functionality.
Tested: Container successfully uses built-in files when local mounts are unavailable.