feat: add session updates and message dialogs

backend/tests/test_runtime_variables.py

@@ -146,6 +146,34 @@ class DynamicVariableTests(unittest.TestCase):
         self.assertEqual(store.values["system__agent_turns"], 1)
         self.assertIn("查订单", store.values["system__conversation_history"])
 
+    def test_session_assignment_is_declared_typed_and_atomic(self):
+        store = DynamicVariableStore(
+            {"panel_open": False, "selection": "none"},
+            variable_types={
+                "panel_open": "boolean",
+                "selection": "string",
+            },
+        )
+
+        changed = store.assign_declared_many(
+            {"panel_open": True, "selection": "confirmed"}
+        )
+        self.assertEqual(changed, ["panel_open", "selection"])
+        self.assertEqual(
+            store.public_values(),
+            {"panel_open": True, "selection": "confirmed"},
+        )
+
+        with self.assertRaisesRegex(DynamicVariableError, "类型应为 boolean"):
+            store.assign_declared_many(
+                {"selection": "cancelled", "panel_open": "yes"}
+            )
+        self.assertEqual(store.values["selection"], "confirmed")
+        self.assertIs(store.values["panel_open"], True)
+
+        with self.assertRaisesRegex(DynamicVariableError, "未声明"):
+            store.assign_declared_many({"unknown_state": True})
+
 
 if __name__ == "__main__":
     unittest.main()