Test: Add tests for chunk API endpoints (#8616)

### What problem does this PR solve?

- Add comprehensive test suite for chunk operations including:
  - Test files for create, list, retrieve, update, and delete chunks
  - Authorization tests
  - Batch operations tests
- Update test configurations and common utilities
- Validate `important_kwd` and `question_kwd` fields are lists in
chunk_app.py
- Reorganize imports and clean up duplicate code

### Type of change

- [x] Add test cases

test/testcases/test_web_api/conftest.py

@@ -13,18 +13,23 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 #
+from time import sleep
+
 import pytest
 from common import (
+    batch_add_chunks,
     batch_create_datasets,
+    bulk_upload_documents,
+    delete_chunks,
+    list_chunks,
+    list_documents,
     list_kbs,
+    parse_documents,
     rm_kb,
 )
-
-# from configs import HOST_ADDRESS, VERSION
 from libs.auth import RAGFlowWebApiAuth
 from pytest import FixtureRequest
-
-# from ragflow_sdk import RAGFlow
+from utils import wait_for
 from utils.file_utils import (
     create_docx_file,
     create_eml_file,
@@ -39,6 +44,15 @@ from utils.file_utils import (
 )
 
 
+@wait_for(30, 1, "Document parsing timeout")
+def condition(_auth, _kb_id):
+    res = list_documents(_auth, {"kb_id": _kb_id})
+    for doc in res["data"]["docs"]:
+        if doc["run"] != "3":
+            return False
+    return True
+
+
 @pytest.fixture
 def generate_test_files(request: FixtureRequest, tmp_path):
     file_creators = {
@@ -73,11 +87,6 @@ def WebApiAuth(auth):
     return RAGFlowWebApiAuth(auth)
 
 
-# @pytest.fixture(scope="session")
-# def client(token: str) -> RAGFlow:
-#     return RAGFlow(api_key=token, base_url=HOST_ADDRESS, version=VERSION)
-
-
 @pytest.fixture(scope="function")
 def clear_datasets(request: FixtureRequest, WebApiAuth: RAGFlowWebApiAuth):
     def cleanup():
@@ -108,3 +117,35 @@ def add_dataset_func(request: FixtureRequest, WebApiAuth: RAGFlowWebApiAuth) ->
 
     request.addfinalizer(cleanup)
     return batch_create_datasets(WebApiAuth, 1)[0]
+
+
+@pytest.fixture(scope="class")
+def add_document(request, WebApiAuth, add_dataset, ragflow_tmp_dir):
+    #     def cleanup():
+    #         res = list_documents(WebApiAuth, {"kb_id": dataset_id})
+    #         for doc in res["data"]["docs"]:
+    #             delete_document(WebApiAuth, {"doc_id": doc["id"]})
+
+    #     request.addfinalizer(cleanup)
+
+    dataset_id = add_dataset
+    return dataset_id, bulk_upload_documents(WebApiAuth, dataset_id, 1, ragflow_tmp_dir)[0]
+
+
+@pytest.fixture(scope="class")
+def add_chunks(request, WebApiAuth, add_document):
+    def cleanup():
+        res = list_chunks(WebApiAuth, {"doc_id": document_id})
+        if res["code"] == 0:
+            chunk_ids = [chunk["chunk_id"] for chunk in res["data"]["chunks"]]
+            delete_chunks(WebApiAuth, {"doc_id": document_id, "chunk_ids": chunk_ids})
+
+    request.addfinalizer(cleanup)
+
+    kb_id, document_id = add_document
+    parse_documents(WebApiAuth, {"doc_ids": [document_id], "run": "1"})
+    condition(WebApiAuth, kb_id)
+    chunk_ids = batch_add_chunks(WebApiAuth, document_id, 4)
+    # issues/6487
+    sleep(1)
+    return kb_id, document_id, chunk_ids