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/crud/site.py

@@ -16,7 +16,6 @@ from app.models.document import Document
 from app.models.document_version import DocumentVersion
 from app.models.distribution import Distribution
 from app.models.drug_shipment import DrugShipment
-from app.models.fee_attachment import FeeAttachment
 from app.models.finance import FinanceItem
 from app.models.kickoff_meeting import KickoffMeeting
 from app.models.precaution import Precaution
@@ -33,7 +32,6 @@ from app.models.visit import Visit
 from app.schemas.site import SiteCreate, SiteUpdate
 
 ATTACHMENT_ROOT = Path(__file__).resolve().parent.parent / "uploads"
-FEE_ATTACHMENT_ROOT = ATTACHMENT_ROOT / "fees"
 DOCUMENT_ATTACHMENT_ROOT = ATTACHMENT_ROOT / "documents"
 
 
@@ -239,24 +237,7 @@ async def delete_site_and_related(db: AsyncSession, site: Site) -> None:
             )
         )
 
-    fee_attachment_paths: list[str] = []
     if contract_fee_ids:
-        fee_attachment_paths.extend(
-            (
-                await db.execute(
-                    select(FeeAttachment.storage_key).where(
-                        FeeAttachment.entity_type == "contract_fee",
-                        FeeAttachment.entity_id.in_(contract_fee_ids),
-                    )
-                )
-            ).scalars().all()
-        )
-        await db.execute(
-            delete(FeeAttachment).where(
-                FeeAttachment.entity_type == "contract_fee",
-                FeeAttachment.entity_id.in_(contract_fee_ids),
-            )
-        )
         await db.execute(delete(ContractFeePayment).where(ContractFeePayment.contract_fee_id.in_(contract_fee_ids)))
 
     if distribution_ids:
@@ -311,7 +292,6 @@ async def delete_site_and_related(db: AsyncSession, site: Site) -> None:
 
     await db.execute(delete(Site).where(Site.id == site_id))
     await _remove_files(attachment_paths, ATTACHMENT_ROOT)
-    await _remove_files(fee_attachment_paths, FEE_ATTACHMENT_ROOT)
     await _remove_files(version_file_paths, DOCUMENT_ATTACHMENT_ROOT)
     await db.commit()