修复数据库波动导致后台掉线

backend/internal/modules/adminauth/repository.go

@@ -92,12 +92,15 @@ func (r *Repository) Login(ctx context.Context, username string, password string
 }
 
 func (r *Repository) FindActiveForToken(ctx context.Context, id uint64, tokenVersion int64) (*model.AdminUser, error) {
+	if r.db == nil {
+		return nil, newTokenDependencyError(ErrDependencyUnavailable)
+	}
 	var admin model.AdminUser
 	if err := r.db.WithContext(ctx).First(&admin, id).Error; err != nil {
 		if errors.Is(err, gorm.ErrRecordNotFound) {
 			return nil, newTokenValidationError("admin_not_found", ErrAdminNotFound)
 		}
-		return nil, err
+		return nil, newTokenDependencyError(err)
 	}
 	if admin.Status != "active" {
 		return nil, newTokenValidationError("admin_disabled", ErrAdminDisabled)
@@ -160,10 +163,15 @@ func (r *Repository) FindByID(ctx context.Context, id uint64) (*AdminDTO, error)
 }
 
 func (r *Repository) FindActiveForPasswordGate(ctx context.Context, id uint64, tokenVersion int64) (*AdminDTO, error) {
-	if _, err := r.FindActiveForToken(ctx, id, tokenVersion); err != nil {
+	admin, err := r.FindActiveForToken(ctx, id, tokenVersion)
+	if err != nil {
 		return nil, err
 	}
-	return r.FindByID(ctx, id)
+	// 认证只需要用户名和强制改密标识；复用已校验的查询结果，避免每个后台请求再查询一次数据库。
+	return &AdminDTO{
+		Username:           admin.Username,
+		PasswordMustChange: admin.PasswordMustChange,
+	}, nil
 }
 
 func (r *Repository) UpdateSupportStatus(ctx context.Context, adminID uint64, status string) error {