Fix: model list (#15860)

### What problem does this PR solve?

Remove tenant_llm call in rag.

### Type of change

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

api/apps/services/dataset_api_service.py

@@ -29,7 +29,6 @@ from api.db.services.knowledgebase_service import KnowledgebaseService
 from api.db.services.connector_service import Connector2KbService
 from api.db.services.task_service import GRAPH_RAPTOR_FAKE_DOC_ID, TaskService
 from api.db.services.user_service import TenantService, UserService, UserTenantService
-from api.db.services.tenant_llm_service import TenantLLMService
 from common.constants import FileSource, StatusEnum
 from api.utils.api_utils import deep_merge, get_parser_config, remap_dictionary_keys, verify_embedding_availability
 
@@ -1276,7 +1275,7 @@ async def search_datasets(tenant_id: str, req: dict):
     :param req: search request containing dataset_ids and other params
     :return: (success, result) or (success, error_message)
     """
-    from api.db.joint_services.tenant_model_service import get_tenant_default_model_by_type
+    from api.db.joint_services.tenant_model_service import get_tenant_default_model_by_type, split_model_name
     from api.db.services.doc_metadata_service import DocMetadataService
     from api.db.services.llm_service import LLMBundle
     from api.db.services.search_service import SearchService
@@ -1315,7 +1314,7 @@ async def search_datasets(tenant_id: str, req: dict):
         return False, "Datasets not found!"
 
     # All datasets must use the same embedding model
-    embd_nms = list(set([TenantLLMService.split_model_name_and_factory(kb.embd_id)[0] for kb in kbs]))
+    embd_nms = list(set([split_model_name(kb.embd_id)[0] for kb in kbs]))
     if len(embd_nms) != 1:
         return False, "Datasets use different embedding models."