fix: make Android tasks use extensions automatically and populate marketplace

mcp_server/background/task_runner.py

@@ -247,6 +247,7 @@ async def run_task(
         print("Running task on agent...")
         task_builder = (
             agent.new_task(goal=task_desc)
+            .with_plugins([])  # The standalone fallback cannot dispatch plugin work.
             .with_name(f"task_{trace_id}")
             .with_trace_recording(enabled=True, path=trace_store.TRACES_DIR)
         )