Fix: implement incremental crawling and use SQLite Backup API for sync

Pro Refactor: Industrial-grade stability, atomic sync, auto-repair, and complete API responses

Fix persistence: increase sync frequency and call sync_to_bucket during crawl loop

Final critical stability fixes: move to ephemeral disk, add auto-repair, and enable WAL mode

Implement atomic sync and safe database recovery to prevent loops

Auto-repair malformed database on startup for hands-off recovery

Final robust storage implementation with automatic sync and improved UI

Implement local runtime with periodic bucket sync for high stability

Fix database corruption issues and add maintenance UI

Add crawler control API and persistent storage support

Initial commit for Hugging Face Spaces deployment