feat(debug-trace): 调试链接权限 + trace_url 落库与按权限下发 (#35)

- user 加 debug_trace_enabled、comparison_record 加 trace_url
- 迁移 f8d3b1e60a27：加两列，down_revision 用 tuple 顺带合并既存双 head(invite_fingerprint_table + 044dce6e9b1f)
- UserOut 加 debug_trace_enabled → /me 与登录响应带出
- ComparisonRecordIn/Out 加 trace_url；upsert 落库
- /compare/records 列表与详情按 user.debug_trace_enabled 下发；详情连 raw_payload 里那份一并抹掉，防权限绕过
- admin 加 POST /users/{id}/debug-trace（operator + 审计），列表带该字段

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Reviewed-on: #35

app/admin/routers/users.py

@@ -13,6 +13,7 @@ from app.admin.schemas.user import (
     AdminUserListItem,
     AdminUserOverview,
     GrantCoinsRequest,
+    SetDebugTraceRequest,
     SetUserStatusRequest,
 )
 from app.models.admin import AdminUser
@@ -77,6 +78,28 @@ def set_user_status(
     return OkResponse()
 
 
+@router.post("/{user_id}/debug-trace", response_model=OkResponse, summary="开关调试链接权限")
+def set_user_debug_trace(
+    user_id: int,
+    body: SetDebugTraceRequest,
+    request: Request,
+    admin: Annotated[AdminUser, Depends(require_role("operator"))],
+    db: AdminDb,
+) -> OkResponse:
+    user = user_repo.get_user_by_id(db, user_id)
+    if user is None:
+        raise HTTPException(status_code=404, detail="用户不存在")
+    before = user.debug_trace_enabled
+    # 业务写 + 审计写同一事务(commit=False),最后一起 commit(同 set_user_status)
+    mutations.set_user_debug_trace(db, user, enabled=body.enabled, commit=False)
+    write_audit(
+        db, admin, action="user.debug_trace.set", target_type="user", target_id=user_id,
+        detail={"before": before, "after": body.enabled}, ip=get_client_ip(request), commit=False,
+    )
+    db.commit()
+    return OkResponse()
+
+
 @router.post("/{user_id}/coins", response_model=OkResponse, summary="手动增减金币(带审计)")
 def grant_user_coins(
     user_id: int,