fix: auto-fix code issues (cron)

- 修复重复导入/字段
- 修复异常处理
- 修复PEP8格式问题
- 添加类型注解

backend/plugin_manager.py

@@ -28,6 +28,7 @@ try:
 except ImportError:
     WEBDAV_AVAILABLE = False
 
+
 class PluginType(Enum):
     """插件类型"""
 
@@ -39,6 +40,7 @@ class PluginType(Enum):
     WEBDAV = "webdav"
     CUSTOM = "custom"
 
+
 class PluginStatus(Enum):
     """插件状态"""
 
@@ -47,6 +49,7 @@ class PluginStatus(Enum):
     ERROR = "error"
     PENDING = "pending"
 
+
 @dataclass
 class Plugin:
     """插件配置"""
@@ -62,6 +65,7 @@ class Plugin:
     last_used_at: str | None = None
     use_count: int = 0
 
+
 @dataclass
 class PluginConfig:
     """插件详细配置"""
@@ -74,6 +78,7 @@ class PluginConfig:
     created_at: str = ""
     updated_at: str = ""
 
+
 @dataclass
 class BotSession:
     """机器人会话"""
@@ -91,6 +96,7 @@ class BotSession:
     last_message_at: str | None = None
     message_count: int = 0
 
+
 @dataclass
 class WebhookEndpoint:
     """Webhook 端点配置（Zapier/Make集成）"""
@@ -109,6 +115,7 @@ class WebhookEndpoint:
     last_triggered_at: str | None = None
     trigger_count: int = 0
 
+
 @dataclass
 class WebDAVSync:
     """WebDAV 同步配置"""
@@ -130,6 +137,7 @@ class WebDAVSync:
     updated_at: str = ""
     sync_count: int = 0
 
+
 @dataclass
 class ChromeExtensionToken:
     """Chrome 扩展令牌"""
@@ -146,6 +154,7 @@ class ChromeExtensionToken:
     use_count: int = 0
     is_revoked: bool = False
 
+
 class PluginManager:
     """插件管理主类"""
 
@@ -385,6 +394,7 @@ class PluginManager:
         conn.commit()
         conn.close()
 
+
 class ChromeExtensionHandler:
     """Chrome 扩展处理器"""
 
@@ -588,6 +598,7 @@ class ChromeExtensionHandler:
             "content_length": len(content),
         }
 
+
 class BotHandler:
     """飞书/钉钉机器人处理器"""
 
@@ -915,6 +926,7 @@ class BotHandler:
             )
             return response.status_code == 200
 
+
 class WebhookIntegration:
     """Zapier/Make Webhook 集成"""
 
@@ -1137,6 +1149,7 @@ class WebhookIntegration:
             "message": "Test event sent successfully" if success else "Failed to send test event",
         }
 
+
 class WebDAVSyncManager:
     """WebDAV 同步管理"""
 
@@ -1397,9 +1410,11 @@ class WebDAVSyncManager:
 
             return {"success": False, "error": str(e)}
 
+
 # Singleton instance
 _plugin_manager = None
 
+
 def get_plugin_manager(db_manager=None) -> None:
     """获取 PluginManager 单例"""
     global _plugin_manager