feat: 移除PDI和订单号字段，新增设备巡检模块

- 从物料跟踪页面移除订单号列和表单字段
- 从导航菜单移除PDI管理，添加设备巡检
- 新增InspectionLocation和InspectionRecord后端模型和API
- 新增设备巡检前端页面（左侧点位列表，右侧设备和历史记录）

backend/app/schemas/downtime.py

@@ -0,0 +1,67 @@
+from pydantic import BaseModel
+from typing import Optional
+from datetime import datetime
+
+
+class CategoryCreate(BaseModel):
+    code: str
+    name: str
+    category: str
+    description: Optional[str] = None
+
+
+class CategoryOut(BaseModel):
+    id: int
+    code: str
+    name: str
+    category: str
+    description: Optional[str]
+    is_active: int
+
+    class Config:
+        from_attributes = True
+
+
+class DowntimeCreate(BaseModel):
+    category_id: Optional[int] = None
+    category_code: Optional[str] = None
+    shift: Optional[str] = None
+    shift_date: Optional[datetime] = None
+    start_time: datetime
+    end_time: Optional[datetime] = None
+    equipment_code: Optional[str] = None
+    fault_desc: Optional[str] = None
+    action_taken: Optional[str] = None
+    root_cause: Optional[str] = None
+    reporter: Optional[str] = None
+    handler: Optional[str] = None
+    is_planned: int = 0
+
+
+class DowntimeUpdate(BaseModel):
+    end_time: Optional[datetime] = None
+    action_taken: Optional[str] = None
+    root_cause: Optional[str] = None
+    handler: Optional[str] = None
+    fault_desc: Optional[str] = None
+
+
+class DowntimeOut(BaseModel):
+    id: int
+    category_code: Optional[str]
+    category_name: Optional[str]
+    shift: Optional[str]
+    shift_date: Optional[datetime]
+    start_time: datetime
+    end_time: Optional[datetime]
+    duration: Optional[float]
+    equipment_code: Optional[str]
+    fault_desc: Optional[str]
+    action_taken: Optional[str]
+    reporter: Optional[str]
+    handler: Optional[str]
+    is_planned: int
+    created_at: datetime
+
+    class Config:
+        from_attributes = True