fix: preserve live session transparency

Author: he-yufeng

src/google/adk/flows/llm_flows/base_llm_flow.py

@@ -517,7 +517,6 @@ async def run_live(
           llm_request.live_connect_config.session_resumption.handle = (
               invocation_context.live_session_resumption_handle
           )
-          llm_request.live_connect_config.session_resumption.transparent = True
 
         logger.info(
             'Establishing live connection for agent: %s',

tests/unittests/flows/llm_flows/test_base_llm_flow.py

@@ -679,6 +679,12 @@ async def mock_receive():
 
         # Verify that send_history was not called because we resumed.
         mock_connection.send_history.assert_not_called()
+        reconnect_request = mock_connect.call_args.args[0]
+        session_resumption = (
+            reconnect_request.live_connect_config.session_resumption
+        )
+        assert session_resumption.handle == 'test_handle'
+        assert session_resumption.transparent is not True
 
 
 @pytest.mark.asyncio