完善后台管理与测试支撑

1、为后台用户列表增加关键词和状态筛选，后端同步支持过滤与总数统计。

2、创建用户时要求填写初始密码，并补充前端校验和自动填充隔离。

3、优化项目管理列表角色展示、项目详情抽屉脏数据保护和审计详情抽屉关闭体验。

4、清理旧费用附件关联、统一测试模型注册，并更新迁移端点和注册筛选测试。

backend/app/api/v1/users.py

@@ -1,6 +1,6 @@
 import uuid
 
-from fastapi import APIRouter, Depends, HTTPException, status
+from fastapi import APIRouter, Depends, HTTPException, Query, status
 from sqlalchemy.ext.asyncio import AsyncSession
 
 from app.core.deps import get_db_session, is_system_admin, require_roles
@@ -8,7 +8,7 @@ from app.schemas.common import PaginatedResponse
 from app.crud import user as user_crud
 from app.crud import member as member_crud
 from app.utils.pagination import paginate
-from app.schemas.user import UserCreate, UserRead, UserUpdate
+from app.schemas.user import UserCreate, UserRead, UserStatus, UserUpdate
 
 router = APIRouter()
 
@@ -17,12 +17,14 @@ router = APIRouter()
 async def list_users(
     skip: int = 0,
     limit: int = 100,
+    keyword: str | None = Query(default=None),
+    user_status: UserStatus | None = Query(default=None, alias="status"),
     db: AsyncSession = Depends(get_db_session),
     current_user=Depends(require_roles(["ADMIN"])),
 ) -> PaginatedResponse[UserRead]:
-    users = await user_crud.list_users(db, skip=skip, limit=limit)
-    total_users = await user_crud.list_users(db, skip=0, limit=10_000_000)
-    return paginate(list(users), total=len(total_users))
+    users = await user_crud.list_users(db, skip=skip, limit=limit, keyword=keyword, status=user_status)
+    total_users = await user_crud.count_users(db, keyword=keyword, status=user_status)
+    return paginate(list(users), total=total_users)
 
 
 @router.post("/", response_model=UserRead, status_code=status.HTTP_201_CREATED)