fix: Remove unused imports and variables to pass Ruff linting

- Comment out unused format_type in export_results (TODO for CSV export)
- Comment out unused req in evaluate_single (TODO for implementation)
- Remove unused json import from evaluation_service
- Remove unused LLMBundle import from evaluation_service
- Remove unused Mock, MagicMock imports from test_evaluation_service
- Keep Mock import in test_evaluation_framework_demo (actually used)

All 24 tests passing ✅

api/apps/evaluation_app.py

@@ -431,7 +431,7 @@ async def compare_runs():
 async def export_results(run_id):
     """Export evaluation results as JSON/CSV"""
     try:
-        format_type = request.args.get("format", "json")
+        # format_type = request.args.get("format", "json")  # TODO: Use for CSV export
         
         result = EvaluationService.get_run_results(run_id)
         
@@ -465,7 +465,7 @@ async def evaluate_single():
     }
     """
     try:
-        req = await get_request_json()
+        # req = await get_request_json()  # TODO: Use for single evaluation implementation
         
         # TODO: Implement single evaluation
         # This would execute the RAG pipeline and return metrics immediately

api/db/services/evaluation_service.py

@@ -26,7 +26,6 @@ Provides functionality for evaluating RAG system performance including:
 """
 
 import logging
-import json
 from typing import List, Dict, Any, Optional, Tuple
 from datetime import datetime
 from timeit import default_timer as timer
@@ -34,7 +33,6 @@ from timeit import default_timer as timer
 from api.db.db_models import EvaluationDataset, EvaluationCase, EvaluationRun, EvaluationResult
 from api.db.services.common_service import CommonService
 from api.db.services.dialog_service import DialogService, chat
-from api.db.services.llm_service import LLMBundle
 from common.misc_utils import get_uuid
 from common.time_utils import current_timestamp
 from common.constants import StatusEnum

test/unit_test/services/test_evaluation_framework_demo.py

@@ -20,7 +20,7 @@ This test doesn't require RAGFlow dependencies.
 """
 
 import pytest
-from unittest.mock import Mock, MagicMock
+from unittest.mock import Mock
 
 
 class TestEvaluationFrameworkDemo:

test/unit_test/services/test_evaluation_service.py

@@ -26,8 +26,7 @@ Tests cover:
 """
 
 import pytest
-from unittest.mock import Mock, patch, MagicMock
-from common.misc_utils import get_uuid
+from unittest.mock import patch
 
 
 class TestEvaluationDatasetManagement: