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/KOBO_SETUP.md

@@ -409,7 +409,7 @@ If you're running Bookhoard with a custom domain or port:
 ```ini
 [Sync]
 # Custom domain
-ServerURL=https://bookmann.example.com/api/sync/kobo
+ServerURL=https://bookhoard.example.com/api/sync/kobo
 
 # Custom port
 ServerURL=http://192.168.1.100:9000/api/sync/kobo
@@ -424,7 +424,7 @@ If you have SSL/TLS configured on Bookhoard:
 
 ```ini
 [Sync]
-ServerURL=https://bookmann.yourdomain.com/api/sync/kobo
+ServerURL=https://bookhoard.yourdomain.com/api/sync/kobo
 ```
 
 Kobo will automatically trust the certificate if properly configured.