feat: 仪表盘+催办在休息日跳过填报检查

- 新增 is_working_day() 工具函数，自动跳过周末 + 可配置法定假日
- 仪表盘填报进度新增 is_rest_day 字段，休息日显示灰「休」印章
- 催办调度改用 is_working_day() 替代原始 weekday 检查
- 系统设置新增「法定节假日」配置卡片，支局长可管理假日日期

Co-Authored-By: Claude <noreply@anthropic.com>

backend/app/services/scheduler.py

@@ -7,16 +7,29 @@ from app.models.user import User
 from app.models.leave import Leave
 from app.models.work_plan import WorkPlan
 from app.models.customer import Customer
+from app.models.system_config import SystemConfig
 from app.services.wecom import wecom_client
-from app.utils.timezone import today_cst
+from app.utils.timezone import today_cst, is_working_day
 
 
 async def check_daily_reporting(db: AsyncSession) -> dict:
     """Check today's reporting progress and send wecom reminders to managers who haven't reported."""
     today = today_cst()
-    weekday = today.weekday()
-    if weekday >= 5:  # Skip weekends
-        return {"status": "weekend", "date": str(today)}
+
+    # Load holiday config
+    holiday_row = await db.get(SystemConfig, "holidays")
+    holidays: set[date] = set()
+    if holiday_row and holiday_row.value:
+        for s in holiday_row.value.split(","):
+            s = s.strip()
+            if s:
+                try:
+                    holidays.add(date.fromisoformat(s))
+                except ValueError:
+                    pass
+
+    if not is_working_day(today, holidays):
+        return {"status": "rest_day", "date": str(today)}
 
     # Get all users who need to report
     result = await db.execute(