feat: 在制品列表信息层级重构 + SLA预警色 + 点击跳转

1. 信息层级重构:
   主信息: [状态Tag] 任务名 | 负责人: 张三  ⏰3h
   附加信息: 物料名 SN:25022 ...A1B2C3  08-12 10:00
   新增后端 material_name 字段, 前端卡片式布局

2. SLA滞留预警色:
   <12h → 绿色(正常) | 12-24h → 橙色(警告) | >24h → 红色加粗(危险)

3. 交互: 点击卡片新窗口打开对应产品扫码详情页

backend/app/services/dashboard_service.py

@@ -30,6 +30,7 @@ class WipTask(BaseModel):
     assignee: str
     product_sn: str
     external_serial: str | None   # 业务序列号
+    material_name: str            # 物料名称
     status: str
     received_at: str
     duration_hours: float
@@ -132,10 +133,10 @@ async def get_wip_tasks(db: AsyncSession, limit: int = 20) -> list[WipTask]:
     from app.core.time_utils import get_beijing_time, BEIJING_TZ
 
     stmt = (
-        select(Task, Product.serial_number, Product.external_serial)
+        select(Task, Product.serial_number, Product.external_serial, Product.material_name)
         .join(Product, Task.product_id == Product.id)
         .where(Task.status.in_([TASK_STATUS_PENDING, TASK_STATUS_WIP]))
-        .limit(limit * 2)  # 多取一些，后面 Python 统一排序
+        .limit(limit * 2)
     )
     result = await db.execute(stmt)
     rows = result.all()
@@ -148,7 +149,7 @@ async def get_wip_tasks(db: AsyncSession, limit: int = 20) -> list[WipTask]:
 
     now = get_beijing_time()
     wip_list: list[WipTask] = []
-    for task, product_sn, ext_sn in rows:
+    for task, product_sn, ext_sn, mat_name in rows:
         start = task.received_at or task.created_at
         if start:
             if start.tzinfo is None:
@@ -167,6 +168,7 @@ async def get_wip_tasks(db: AsyncSession, limit: int = 20) -> list[WipTask]:
             assignee=name_map.get(task.assignee_id or "", task.assignee_id or "未分配"),
             product_sn=product_sn or "",
             external_serial=ext_sn or None,
+            material_name=mat_name or "",
             status=task.status,
             received_at=recv_str,
             duration_hours=hours,