fix(backend): allow admins to download submitted agents pending review

The get_graph_as_admin() function had an access check that required the
graph to be either owned by the requesting user or published (APPROVED) in
the marketplace. This caused admin download of submitted-but-not-yet-approved
agents to fail with a NotFoundError, surfacing as a Server Components render
error in the frontend.

Since get_graph_as_admin is only called from admin-protected routes, the
ownership/marketplace check is redundant — route-level auth already ensures
only admins can access these endpoints. The fix removes the check, keeping
only the null guard.

autogpt_platform/backend/backend/data/graph.py

@@ -1207,13 +1207,9 @@ async def get_graph_as_admin(
         order={"version": "desc"},
     )
 
-    # For access, the graph must be owned by the user or listed in the store
-    if graph is None or (
-        graph.userId != user_id
-        and not await is_graph_published_in_marketplace(
-            graph_id, version or graph.version
-        )
-    ):
+    # Admin access bypasses ownership and marketplace checks — route-level
+    # auth already ensures only admins can call this function.
+    if graph is None:
         return None
 
     if for_export: