fix: UID 类型混用统一（uint ↔ string）

- Comment.ReplyToUID string→uint, 移除 varchar(36) gorm 约束
- CommentMention.UID string→uint, 移除 varchar(36) gorm 约束
- UserSearchResult.UID string→uint
- 移除 SearchUsersByLevel 中 strconv.FormatUint 转换
- 删除 GetUserUIDByID 方法，CreateReply 直接使用 parent.UserID
- fillReplyToNames 使用 map[uint]string 替代 map[string]string
- 更新 commentStore 接口声明
- 修复前端 mention 下拉 show.html 中 u.id→u.uid

internal/model/comment.go

@@ -8,7 +8,7 @@ type Comment struct {
 	PostID       uint      `gorm:"index;not null" json:"post_id"`
 	RootID       uint      `gorm:"index;not null" json:"root_id"`    // 根评论ID，顶级评论指向自身
 	ParentID     *uint     `gorm:"index" json:"parent_id"`           // 父评论ID，NULL=顶级评论
-	ReplyToUID   string    `gorm:"type:varchar(36);default:''" json:"reply_to_uid"` // 被回复者UID
+	ReplyToUID   uint      `gorm:"default:0" json:"reply_to_uid"` // 被回复者UID
 	Body         string    `gorm:"type:text;not null" json:"body"`   // 评论内容（纯文本 + 图片URL）
 	IsDeleted    bool      `gorm:"default:false;index" json:"is_deleted"`
 	LikesCount   int       `gorm:"default:0" json:"likes_count"`
@@ -31,12 +31,12 @@ type Comment struct {
 type CommentMention struct {
 	ID        uint   `gorm:"primarykey" json:"id"`
 	CommentID uint   `gorm:"uniqueIndex:idx_comment_uid,priority:1;not null" json:"comment_id"`
-	UID       string `gorm:"type:varchar(36);uniqueIndex:idx_comment_uid,priority:2;not null" json:"uid"`
+	UID       uint   `gorm:"uniqueIndex:idx_comment_uid,priority:2;not null" json:"uid"`
 }
 
 // UserSearchResult @搜索用户结果
 type UserSearchResult struct {
-	UID      string `json:"uid"`
+	UID      uint   `json:"uid"`
 	Username string `json:"username"`
 	Level    int    `json:"level"`
 }

internal/repository/comment_mention_repo.go

@@ -1,8 +1,6 @@
 package repository
 
 import (
-	"strconv"
-
 	"metazone.cc/metalab/internal/model"
 	"metazone.cc/metalab/internal/service"
 )
@@ -21,7 +19,7 @@ func (r *CommentRepo) FindMentionsByComment(commentID uint) ([]model.CommentMent
 
 // SearchUsersByLevel 搜索指定等级及以上用户（用于@艾特），返回 uid/username/exp
 func (r *CommentRepo) SearchUsersByLevel(keyword string, minLevel int, limit int) ([]struct {
-	UID      string
+	UID      uint
 	Username string
 	Exp      int
 }, error) {
@@ -42,30 +40,20 @@ func (r *CommentRepo) SearchUsersByLevel(keyword string, minLevel int, limit int
 		Find(&list).Error
 
 	var res []struct {
-		UID      string
+		UID      uint
 		Username string
 		Exp      int
 	}
 	for _, u := range list {
 		res = append(res, struct {
-			UID      string
+			UID      uint
 			Username string
 			Exp      int
-		}{UID: strconv.FormatUint(uint64(u.UID), 10), Username: u.Username, Exp: u.Exp})
+		}{UID: u.UID, Username: u.Username, Exp: u.Exp})
 	}
 	return res, err
 }
 
-// GetUserUIDByID 通过 uint ID 获取 user 的 UID 字符串
-func (r *CommentRepo) GetUserUIDByID(userID uint) (string, error) {
-	var uid uint
-	err := r.db.Table("users").Select("id").Where("id = ?", userID).Scan(&uid).Error
-	if err != nil {
-		return "", err
-	}
-	return strconv.FormatUint(uint64(uid), 10), nil
-}
-
 // GetUsernameByID 通过 userID 获取用户名（用于通知内容）
 func (r *CommentRepo) GetUsernameByID(userID uint) (string, error) {
 	var username string

internal/repository/comment_repo.go

@@ -96,7 +96,7 @@ func (r *CommentRepo) fillReplyToNames(list []model.Comment) {
 		return
 	}
 	type nameRow struct {
-		UID      string
+		UID      uint
 		Username string
 	}
 	var rows []nameRow
@@ -105,12 +105,12 @@ func (r *CommentRepo) fillReplyToNames(list []model.Comment) {
 		Where("id IN (SELECT reply_to_uid FROM comments WHERE root_id IN (?) AND parent_id IS NOT NULL)", r.rootIDsFromList(list)).
 		Find(&rows)
 
-	m := make(map[string]string)
+	m := make(map[uint]string)
 	for _, row := range rows {
 		m[row.UID] = row.Username
 	}
 	for i := range list {
-		if list[i].ReplyToUID != "" {
+		if list[i].ReplyToUID != 0 {
 			list[i].ReplyToName = m[list[i].ReplyToUID]
 		}
 	}

internal/service/comment_service.go

@@ -93,10 +93,7 @@ func (s *CommentService) CreateReply(userID uint, parentID uint, body string) (*
 		ParentID:   &parentID,
 		Body:       body,
 		UserID:     userID,
-	}
-	// 获取被回复者UID
-	if replyToUID, err := s.repo.GetUserUIDByID(parent.UserID); err == nil {
-		comment.ReplyToUID = replyToUID
+		ReplyToUID: parent.UserID,
 	}
 
 	if err := s.repo.Create(comment); err != nil {

internal/service/repository.go

@@ -154,11 +154,10 @@ type commentStore interface {
 	FindPostIDByComment(commentID uint) (uint, error)
 	FindPostAuthorID(postID uint) (uint, error)
 	SearchUsersByLevel(keyword string, minLevel, limit int) ([]struct {
-		UID      string
+		UID      uint
 		Username string
 		Exp      int
 	}, error)
-	GetUserUIDByID(userID uint) (string, error)
 	GetUsernameByID(userID uint) (string, error)
 	ListAllComments(keyword string, showDeleted bool, offset, limit int) ([]model.AdminCommentRow, int64, error)
 }

templates/MetaLab-2026/html/posts/show.html

@@ -931,7 +931,7 @@
             let u = users[i];
             var item = document.createElement('div');
             item.className = 'mention-item';
-            item.innerHTML = '<span class="mention-username">' + escapeHtml(u.username) + '</span><span class="mention-uid">' + escapeHtml(u.id) + '</span>';
+            item.innerHTML = '<span class="mention-username">' + escapeHtml(u.username) + '</span><span class="mention-uid">' + escapeHtml(u.uid) + '</span>';
             item.addEventListener('mousedown', function(e) {
                 e.preventDefault();
                 selectMention(u);