fix(时长): 所有时长计算排除非工作日 + 修复两处时区多算8小时

- get_wip_tasks/get_people_workload/get_people_history/product active_duration_hours/analytics 均改用 working_duration_hours
- 修复 get_wip_tasks 与 active_duration_hours 的 naive 时间误标北京时间 bug(DB实存UTC，原多算8小时)
- 每处读取 holidays 表排除配置的放假日期

backend/app/services/dashboard_service.py

@@ -209,7 +209,12 @@ async def get_dashboard_stats(
 async def get_wip_tasks(db: AsyncSession, limit: int = 20) -> list[WipTask]:
     from app.models.task import Task, TASK_STATUS_PENDING, TASK_STATUS_WIP
     from app.models.product import Product
-    from app.core.time_utils import get_beijing_time, BEIJING_TZ
+    from app.models.holiday import Holiday
+    from app.core.time_utils import get_beijing_time, to_beijing, working_duration_hours
+
+    # 读取节假日（排除非工作日）
+    hres = await db.execute(select(Holiday.day))
+    holidays = {r[0] for r in hres}
 
     stmt = (
         select(Task, Product.serial_number, Product.external_serial, Product.material_name, Product.spec_model)
@@ -231,12 +236,9 @@ async def get_wip_tasks(db: AsyncSession, limit: int = 20) -> list[WipTask]:
     for task, product_sn, ext_sn, mat_name, spec in rows:
         start = task.received_at or task.created_at
         if start:
-            if start.tzinfo is None:
-                start = start.replace(tzinfo=BEIJING_TZ)
-            else:
-                start = start.astimezone(BEIJING_TZ)
-            hours = round((now - start).total_seconds() / 3600, 1)
-            recv_str = start.strftime("%m-%d %H:%M")
+            start_bj = to_beijing(start)  # 🚀 naive 按 UTC 转北京时间（修复多算8小时）
+            hours = working_duration_hours(start_bj, now, holidays)
+            recv_str = start_bj.strftime("%m-%d %H:%M")
         else:
             hours = 0
             recv_str = ""
@@ -683,7 +685,12 @@ async def get_people_workload(db: AsyncSession) -> list[PersonWorkload]:
     """上帝视角 — 按负责人聚合当前在制品设备（WIP/PENDING 任务，product 去重，含滞留时长）。"""
     from app.models.task import Task, TASK_STATUS_PENDING, TASK_STATUS_WIP
     from app.models.product import Product
-    from app.core.time_utils import get_beijing_time, BEIJING_TZ
+    from app.models.holiday import Holiday
+    from app.core.time_utils import get_beijing_time, to_beijing, working_duration_hours
+
+    # 读取节假日（排除非工作日）
+    hres = await db.execute(select(Holiday.day))
+    holidays = {r[0] for r in hres}
 
     stmt = (
         select(
@@ -749,7 +756,7 @@ async def get_people_workload(db: AsyncSession) -> list[PersonWorkload]:
         devices: list[PersonDevice] = []
         for product_id, e in prods.items():
             dt = e["earliest_dt"]
-            hours = round((now - dt).total_seconds() / 3600, 1) if dt else 0.0
+            hours = working_duration_hours(dt, now, holidays) if dt else 0.0
             received_str = dt.strftime("%m-%d %H:%M") if dt else None
             devices.append(PersonDevice(
                 product_id=product_id,
@@ -787,11 +794,16 @@ async def get_people_history(
     """上帝视角 — 人员效能与工时台账（平铺 Task 明细，含 WIP/PENDING/COMPLETED）。"""
     from app.models.task import Task, TASK_STATUS_WIP, TASK_STATUS_PENDING, TASK_STATUS_COMPLETED
     from app.models.product import Product
-    from app.core.time_utils import get_beijing_time, BEIJING_TZ
+    from app.core.time_utils import get_beijing_time, BEIJING_TZ, to_beijing, working_duration_hours
+    from app.models.holiday import Holiday
     from sqlalchemy import func
 
     now = get_beijing_time()
 
+    # 读取节假日（排除非工作日）
+    hres = await db.execute(select(Holiday.day))
+    holidays = {r[0] for r in hres}
+
     # ── 关联 TaskRecord：最新有效备注 + 记录总数 ──
     from app.models.task import TaskRecord
     from sqlalchemy import and_, or_
@@ -915,7 +927,7 @@ async def get_people_history(
         else:
             end_dt = now
             completed_str = None
-        hours = round((end_dt - received_dt).total_seconds() / 3600, 1) if received_dt else 0.0
+        hours = working_duration_hours(received_dt, end_dt, holidays) if received_dt else 0.0
         records.append(PersonHistoryRecord(
             task_id=str(row[0]),
             task_name=row[1] or "",