* Implement maintenance page with task and log display
* Add backfill and metadata retry functionality
* Integrate grid component for project display in thoughts page
* Update types for maintenance tasks and logs
* Enhance sidebar and shell for new maintenance navigation
- Add schema/*.dbml covering all existing tables (001-019)
- Wire relspecgo via make generate-migrations target
- Add make check-schema-drift for CI drift detection
- Add schema/README.md documenting the DBML-first workflow
Closes#19
