refactor: remove legacy assistant compatibility

backend/tests/test_tool_policy.py

@@ -24,19 +24,9 @@ def runtime_tool(tool_type: str, config: dict | None = None) -> RuntimeTool:
 
 
 class ToolPolicyTests(unittest.TestCase):
-    def test_backwards_compatible_execution_defaults(self):
-        self.assertEqual(
-            policy_for_tool(runtime_tool("http")).execution_mode,
-            "immediate",
-        )
-        self.assertEqual(
-            policy_for_tool(runtime_tool("client")).execution_mode,
-            "async",
-        )
-        self.assertEqual(
-            policy_for_tool(runtime_tool("client")).response_wait_mode,
-            "timeout",
-        )
+    def test_missing_current_policy_is_rejected(self):
+        with self.assertRaises(KeyError):
+            policy_for_tool(runtime_tool("http"))
 
     def test_explicit_policy_is_normalized(self):
         policy = policy_for_tool(
@@ -55,6 +45,22 @@ class ToolPolicyTests(unittest.TestCase):
         self.assertFalse(policy.wait_for_response)
         self.assertEqual(policy.response_wait_mode, "session")
 
+    def test_non_client_tools_use_fixed_response_wait_policy(self):
+        policy = policy_for_tool(
+            runtime_tool(
+                "http",
+                {
+                    "allow_interruptions": True,
+                    "execution_mode": "async",
+                },
+            )
+        )
+
+        self.assertTrue(policy.allow_interruptions)
+        self.assertEqual(policy.execution_mode, "async")
+        self.assertTrue(policy.wait_for_response)
+        self.assertEqual(policy.response_wait_mode, "timeout")
+
 
 class ToolInterruptionStrategyTests(unittest.IsolatedAsyncioTestCase):
     async def test_releases_only_after_tool_and_following_speech_finish(self):