fix: 修复通知系统链接错误、标记已读失败及帖子404页渲染异常

- 修复 post_rejected 通知链接到帖子详情页（原来链接到 /studio/posts）
- 为 audit_approved/audit_rejected 通知添加链接到 /settings
- 通知已读标记改用 fetch keepalive 代替 sendBeacon，附带 CSRF token，避免页面跳转时请求丢失
- 修复 repository 层 id 列名应为 uid（BaseModel 定义 primarykey column:uid）
- 帖子404页添加 ExtraCSS 引入 posts.css，修复 SVG 图标无尺寸约束全屏渲染异常

internal/repository/notification_repo.go

@@ -50,7 +50,7 @@ func (r *NotificationRepo) CountUnread(userID uint) (int64, error) {
 // MarkRead 标记单条消息为已读
 func (r *NotificationRepo) MarkRead(id, userID uint) error {
 	return r.db.Model(&model.Notification{}).
-		Where("id = ? AND user_id = ?", id, userID).
+		Where("uid = ? AND user_id = ?", id, userID).
 		Update("is_read", true).Error
 }
 

internal/repository/post_repo.go

@@ -37,7 +37,7 @@ func (r *PostRepo) FindByIDWithAuthor(id uint) (*model.Post, error) {
 	err := r.db.Table("posts").
 		Select("posts.*, users.username as author_name").
 		Joins("LEFT JOIN users ON users.uid = posts.user_id").
-		Where("posts.id = ?", id).
+		Where("posts.uid = ?", id).
 		First(&post).Error
 	if err != nil {
 		return nil, err
@@ -157,7 +157,7 @@ func (r *PostRepo) CountPending() (int64, error) {
 
 // Restore 恢复软删除
 func (r *PostRepo) Restore(id uint) error {
-	result := r.db.Unscoped().Model(&model.Post{}).Where("id = ?", id).Update("deleted_at", nil)
+	result := r.db.Unscoped().Model(&model.Post{}).Where("uid = ?", id).Update("deleted_at", nil)
 	if result.Error != nil {
 		return result.Error
 	}