refactor(workflow): simplify edge configuration

backend/tests/test_workflow_v3.py

@@ -132,6 +132,17 @@ class WorkflowGraphTests(unittest.TestCase):
         self.assertEqual(cleaned_agent["data"]["entryMode"], "wait_user")
         self.assertNotIn("entrySpeech", cleaned_agent["data"])
 
+    def test_edge_speech_fields_are_removed(self):
+        graph = valid_graph()
+        graph["edges"][0]["data"]["transitionSpeech"] = "不再播放"
+        graph["edges"][1]["data"]["transition_speech"] = "旧字段也不再播放"
+
+        normalized = normalize_graph(graph)
+
+        for edge in normalized["edges"]:
+            self.assertNotIn("transitionSpeech", edge["data"])
+            self.assertNotIn("transition_speech", edge["data"])
+
     def test_action_defaults_preserve_legacy_result_assignment_behavior(self):
         graph = valid_graph()
         graph["nodes"].extend(