fix: MySQL 连接池配置优化，防止定时任务连接断开

- config.py: 从 DSN 字符串改为 dict 配置，加入 minsize/maxsize/connect_timeout
- scheduler.py: company_cleaning_job 执行前先 SELECT 1 检查连接可用性

app/core/scheduler.py

@@ -181,8 +181,17 @@ async def _get_active_proxy() -> "str | None":
 
 async def company_cleaning_job():
     """每5分钟执行：自动清洗待处理公司数据"""
+    from tortoise import Tortoise
     from app.services.company_cleaner import company_cleaner
 
+    # 检查连接池是否可用，不可用则跳过本轮
+    try:
+        conn = Tortoise.get_connection("default")
+        await conn.execute_query("SELECT 1")
+    except Exception as e:
+        logger.warning(f"company_cleaning_job skipped: DB connection unavailable: {e}")
+        return
+
     task_id = str(uuid.uuid4())
     started_at = datetime.now()
     task_name = "company_cleaning_job"

app/settings/config.py

@@ -49,7 +49,20 @@ class Settings(BaseSettings):
     ALERT_WINDOW_MINUTES: int = 10
     TORTOISE_ORM: dict = {
         "connections": {
-            "default": "mysql://root:jobdata123@121.4.126.241:3306/job_data"
+            "default": {
+                "engine": "tortoise.backends.mysql",
+                "credentials": {
+                    "host": "121.4.126.241",
+                    "port": 3306,
+                    "user": "root",
+                    "password": "jobdata123",
+                    "database": "job_data",
+                    "minsize": 1,
+                    "maxsize": 10,
+                    "connect_timeout": 10,
+                    "charset": "utf8mb4",
+                },
+            },
         },
         "apps": {
             "models": {