- Item CRUD: getAllItems with category join, getById, create, update, delete
- Category CRUD: getAll ordered by name, create, update, delete with reassignment
- Totals: per-category aggregates and global totals via SQL SUM/COUNT
- All 20 service tests passing
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>