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.

bruno/sidecar/Download Device Sidecar File.bru

@@ -15,5 +15,5 @@ get {
 assert {
   response.status == 200
   response.headers["Content-Type"] contains "application/json"
-  response.headers["Content-Disposition"] contains ".bookmann.json"
+  response.headers["Content-Disposition"] contains ".bookhoard.json"
 }