Update documentation and API tests: Bookmann → Bookhoard

Documentation updates:
- All docs/ files: Update project references
- Bruno API collection: Update collection name and tests
- Device setup guides: Update all examples
- Implementation plan: Update database schema examples
- README files: Update project references

Part of project rename to Bookhoard.

docs/devices/KOREADER_SETUP.md

@@ -69,7 +69,7 @@ Before you begin, make sure you have:
 Find your Bookhoard instance URL. This will typically be one of:
 - **Local Network**: `http://YOUR_COMPUTER_IP:8765`
 - **Localhost (if testing)**: `http://localhost:8765`
-- **Domain (if configured)**: `https://bookmann.yourdomain.com`
+- **Domain (if configured)**: `https://bookhoard.yourdomain.com`
 
 ### Step 2: Register Your Device in Bookhoard