refactor: 清理代码质量和移除未使用文件

- 移除未使用的导入语句和变量
- 修复代码风格问题（空格、格式化等）
- 删除备份文件和测试文件
- 改进异常处理链式调用
- 添加权限系统数据库模型和配置
- 更新版本号至6.4.4
- 优化SQL查询使用正确的布尔表达式

src/llm_models/model_client/gemini_client.py

@@ -12,13 +12,25 @@ from google.generativeai.types import (
 
 try:
     # 尝试从较新的API导入
-    from google.generativeai import configure
     from google.generativeai.types import SafetySetting, GenerationConfig
 except ImportError:
     # 回退到基本类型
     SafetySetting = Dict
     GenerationConfig = Dict
 
+from src.config.api_ada_configs import ModelInfo, APIProvider
+from src.common.logger import get_logger
+from .base_client import APIResponse, UsageRecord, BaseClient, client_registry
+from ..exceptions import (
+    RespParseException,
+    NetworkConnectionError,
+    RespNotOkException,
+    ReqAbortException,
+)
+from ..payload_content.message import Message, RoleType
+from ..payload_content.resp_format import RespFormat, RespFormatType
+from ..payload_content.tool_option import ToolOption, ToolParam, ToolCall
+
 # 定义兼容性类型
 ContentDict = Dict
 PartDict = Dict
@@ -50,20 +62,6 @@ class UnsupportedFunctionError(Exception):
 class FunctionInvocationError(Exception):
     pass
 
-from src.config.api_ada_configs import ModelInfo, APIProvider
-from src.common.logger import get_logger
-
-from .base_client import APIResponse, UsageRecord, BaseClient, client_registry
-from ..exceptions import (
-    RespParseException,
-    NetworkConnectionError,
-    RespNotOkException,
-    ReqAbortException,
-)
-from ..payload_content.message import Message, RoleType
-from ..payload_content.resp_format import RespFormat, RespFormatType
-from ..payload_content.tool_option import ToolOption, ToolParam, ToolCall
-
 logger = get_logger("Gemini客户端")
 
 SAFETY_SETTINGS = [