Make document change-status idempotent for Infinity doc store (#12717)

### What problem does this PR solve?

This PR makes the document change‑status endpoint idempotent under the
Infinity doc store. If a document already has the requested status, the
handler returns success without touching the engine, preventing
unnecessary updates and avoiding missing‑table errors while keeping
responses consistent.

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

test/testcases/test_http_api/test_chat_assistant_management/conftest.py

@@ -14,7 +14,7 @@
 #  limitations under the License.
 #
 import pytest
-from common import batch_create_chat_assistants, delete_chat_assistants, list_documents, parse_documents
+from common import batch_create_chat_assistants, delete_chat_assistants, list_chat_assistants, list_documents, parse_documents
 from utils import wait_for
 
 
@@ -38,3 +38,12 @@ def add_chat_assistants_func(request, HttpApiAuth, add_document):
     parse_documents(HttpApiAuth, dataset_id, {"document_ids": [document_id]})
     condition(HttpApiAuth, dataset_id)
     return dataset_id, document_id, batch_create_chat_assistants(HttpApiAuth, 5)
+
+
+@pytest.fixture(scope="function")
+def chat_assistant_llm_model_type(HttpApiAuth, add_chat_assistants_func):
+    _, _, chat_assistant_ids = add_chat_assistants_func
+    res = list_chat_assistants(HttpApiAuth, {"id": chat_assistant_ids[0]})
+    if res.get("code") == 0 and res.get("data"):
+        return res["data"][0].get("llm", {}).get("model_type", "chat")
+    return "chat"

test/testcases/test_http_api/test_chat_assistant_management/test_update_chat_assistant.py

@@ -100,7 +100,7 @@ class TestChatAssistantUpdate:
     @pytest.mark.parametrize(
         "llm, expected_code, expected_message",
         [
-            ({}, 100, "ValueError"),
+            ({}, 0, ""),
             ({"model_name": "glm-4"}, 0, ""),
             ({"model_name": "unknown"}, 102, "`model_name` unknown doesn't exist"),
             ({"temperature": 0}, 0, ""),
@@ -131,9 +131,11 @@ class TestChatAssistantUpdate:
             pytest.param({"unknown": "unknown"}, 0, "", marks=pytest.mark.skip),
         ],
     )
-    def test_llm(self, HttpApiAuth, add_chat_assistants_func, llm, expected_code, expected_message):
+    def test_llm(self, HttpApiAuth, add_chat_assistants_func, chat_assistant_llm_model_type, llm, expected_code, expected_message):
         dataset_id, _, chat_assistant_ids = add_chat_assistants_func
-        payload = {"name": "llm_test", "dataset_ids": [dataset_id], "llm": llm}
+        llm_payload = dict(llm)
+        llm_payload.setdefault("model_type", chat_assistant_llm_model_type)
+        payload = {"name": "llm_test", "dataset_ids": [dataset_id], "llm": llm_payload}
         res = update_chat_assistant(HttpApiAuth, chat_assistant_ids[0], payload)
         assert res["code"] == expected_code
         if expected_code == 0: