feat: fully defined response code descriptions

Only done on three endpoints. This is a lot of repeated text.

src/organisation/dependencies.py

@@ -58,7 +58,7 @@ def get_org_model_body(
 ) -> type[Org]:
 	org_id: Optional[int] = getattr(request_model, "organisation_id", None)
 	if org_id is None:
-		raise OrgNotFoundException
+		raise OrgNotFoundException()
 
 	return get_org_model(db, request, org_id)