refactor: rename idp fields to provider naming

backend/app/repositories/users_repo.py

@@ -54,13 +54,13 @@ class UsersRepository:
         display_name: str | None,
         is_active: bool,
         status: str = "active",
-        idp_user_id: str | None = None,
+        provider_user_id: str | None = None,
     ) -> User:
         user = self.get_by_sub(user_sub)
         if user is None:
             user = User(
                 user_sub=user_sub,
-                idp_user_id=idp_user_id,
+                provider_user_id=provider_user_id,
                 username=username,
                 email=email,
                 display_name=display_name,
@@ -69,8 +69,8 @@ class UsersRepository:
             )
             self.db.add(user)
         else:
-            if idp_user_id is not None:
-                user.idp_user_id = idp_user_id
+            if provider_user_id is not None:
+                user.provider_user_id = provider_user_id
             user.username = username
             user.email = email
             user.display_name = display_name