fix: 增加MySQL重试机制中的错误代码2003并调整相关逻辑

DB.py

@@ -93,7 +93,7 @@ video_author = Table(
 
 
 def mysql_retry(max_retries: int = 3, base_delay: float = 10):
-    RETRIABLE_ERRORS = {2013, 1213, 2006, 1205}  # 增加 1205
+    RETRIABLE_ERRORS = {2003, 2013, 1213, 2006, 1205} # 增加 1205
 
     def decorator(fn):
         @functools.wraps(fn)
@@ -109,6 +109,7 @@ def mysql_retry(max_retries: int = 3, base_delay: float = 10):
                         raise
 
                     reason = {
+                        2003: "无法连接数据库（超时）",
                         2013: "连接断开",
                         1213: "死锁冲突",
                         2006: "连接失效",
@@ -119,7 +120,7 @@ def mysql_retry(max_retries: int = 3, base_delay: float = 10):
                     logger.warning(
                         f"[MySQL][{fn.__name__}] 第{attempt}次重试（{errno} {reason}）：{e}，等待 {wait:.1f}s...")
 
-                    if errno in {2013, 2006}:
+                    if errno in {2003, 2013, 2006}:
                         self._reconnect_mysql()
                     if errno == 1205:
                         wait = base_delay + 5  # 比如锁等待固定加一点延迟