chore: expose an endpoint for detailed app info

Co-authored-by: Yifan Wang <wanyif@google.com>
PiperOrigin-RevId: 869375052

Author: wyf7107

src/google/adk/cli/adk_web_server.py

@@ -794,6 +794,11 @@ async def get_trace_dict(event_id: str) -> Any:
         raise HTTPException(status_code=404, detail="Trace not found")
       return event_dict
 
+    @app.get("/apps/{app_name}")
+    async def get_app_info(app_name: str) -> Any:
+      runner = await self.get_runner_async(app_name)
+      return runner.app
+
     @app.get("/debug/trace/session/{session_id}", tags=[TAG_DEBUG])
     async def get_session_trace(session_id: str) -> Any:
       spans = memory_exporter.get_finished_spans(session_id)