完善项目权限前置依赖保存校验

- 以接口权限定义中的 prerequisite_permissions 作为前置依赖单一事实源，生成运行时前置权限映射\n- 保存项目角色权限前预检缺失前置权限与受影响下游权限，未确认时返回 409 调整详情\n- 确认保存时自动合并补齐前置权限与取消下游权限，并提供有效权限矩阵读取接口\n- 前端角色权限编辑改为保存时执行依赖校验，弹窗展示需补充前置权限和受影响下游权限\n- 新增编辑权限取消按钮，清理权限选择即时确认弹窗残留\n- 补充后端接口测试、前端权限编辑测试与优化设计文档

backend/app/api/v1/api_permissions.py

@@ -12,6 +12,8 @@ from sqlalchemy.ext.asyncio import AsyncSession
 from app.core.deps import get_current_user, get_db_session, is_system_admin, require_study_member, require_system_permission
 from app.core.project_permissions import (
     get_api_endpoint_permissions,
+    get_effective_api_endpoint_permissions,
+    PrerequisitePermissionConfirmationRequired,
     replace_api_endpoint_permissions,
     get_missing_prerequisites,
 )
@@ -173,7 +175,7 @@ async def get_my_study_api_permissions(
 
     membership = await member_crud.get_member(db, study_id, current_user.id)
     role = membership.role_in_study if membership and membership.is_active else ""
-    permissions = await get_api_endpoint_permissions(db, study_id)
+    permissions = await get_effective_api_endpoint_permissions(db, study_id)
     role_permissions = permissions.get(role, {})
     return {
         role: {
@@ -232,6 +234,7 @@ async def get_study_api_permissions(
 async def update_study_api_permissions(
     study_id: uuid.UUID,
     payload: dict[str, dict[str, bool]],
+    confirm_prerequisite_adjustments: bool = False,
     _=Depends(require_system_permission("system:permissions:project_config")),
     current_user=Depends(get_current_user),
     db: Annotated[AsyncSession, Depends(get_db_session)] = None,
@@ -259,7 +262,22 @@ async def update_study_api_permissions(
             )
 
     # 替换权限配置
-    await replace_api_endpoint_permissions(db, study_id, payload)
+    try:
+        await replace_api_endpoint_permissions(
+            db,
+            study_id,
+            payload,
+            confirm_prerequisite_adjustments=confirm_prerequisite_adjustments,
+        )
+    except PrerequisitePermissionConfirmationRequired as exc:
+        raise HTTPException(
+            status_code=status.HTTP_409_CONFLICT,
+            detail={
+                "code": "PREREQUISITE_PERMISSION_CONFIRMATION_REQUIRED",
+                "message": "需要确认前置权限调整",
+                "adjustments": exc.adjustments,
+            },
+        ) from exc
 
     # 返回更新后的权限矩阵
     permissions = await get_api_endpoint_permissions(db, study_id)