chore(ci, dto): update build workflow and enhance post DTOs

- Added NODE_NO_WARNINGS environment variable to build and deploy workflows.
- Upgraded actions/upload-artifact and actions/download-artifact to version 4 in the build workflow.
- Introduced ContentEditedAt field in PostResponse and PostDetailResponse DTOs to track content modification timestamps.
- Updated post conversion functions to include ContentEditedAt in responses.
- Ensured ContentEditedAt is set during post updates in the repository.

internal/repository/comment_repo.go

@@ -73,6 +73,7 @@ func (r *CommentRepository) Delete(id string) error {
 				UpdateColumns(map[string]interface{}{
 					"comments_count": gorm.Expr("comments_count - 1"),
 					"hot_score":      gorm.Expr("likes_count * 2 + (comments_count - 1) * 3 + views_count * 0.1"),
+					"updated_at":     gorm.Expr("updated_at"),
 				}).Error; err != nil {
 				return err
 			}
@@ -102,6 +103,7 @@ func (r *CommentRepository) ApplyPublishedStats(comment *model.Comment) error {
 			UpdateColumns(map[string]any{
 				"comments_count": gorm.Expr("comments_count + 1"),
 				"hot_score":      gorm.Expr("likes_count * 2 + (comments_count + 1) * 3 + views_count * 0.1"),
+				"updated_at":     gorm.Expr("updated_at"),
 			}).Error; err != nil {
 			return err
 		}

internal/repository/post_repo.go

@@ -61,7 +61,8 @@ func (r *PostRepository) Create(post *model.Post, images []string) error {
 			}
 		}
 
-		return nil
+		// 新建帖子：保证 updated_at 与 created_at 一致（避免历史 NULL/库默认值导致前端误判为已编辑）
+		return tx.Model(post).Where("id = ?", post.ID).UpdateColumn("updated_at", post.CreatedAt).Error
 	})
 }
 
@@ -77,14 +78,18 @@ func (r *PostRepository) GetByID(id string) (*model.Post, error) {
 
 // Update 更新帖子
 func (r *PostRepository) Update(post *model.Post) error {
-	post.UpdatedAt = time.Now()
+	now := time.Now()
+	post.UpdatedAt = now
+	post.ContentEditedAt = &now
 	return r.db.Save(post).Error
 }
 
 // UpdateWithImages 更新帖子及其图片（images=nil 表示不更新图片）
 func (r *PostRepository) UpdateWithImages(post *model.Post, images *[]string) error {
 	return r.db.Transaction(func(tx *gorm.DB) error {
-		post.UpdatedAt = time.Now()
+		now := time.Now()
+		post.UpdatedAt = now
+		post.ContentEditedAt = &now
 		if err := tx.Save(post).Error; err != nil {
 			return err
 		}
@@ -120,6 +125,7 @@ func (r *PostRepository) UpdateModerationStatus(postID string, status model.Post
 		"reviewed_at":   gorm.Expr("CURRENT_TIMESTAMP"),
 		"reviewed_by":   reviewedBy,
 		"reject_reason": rejectReason,
+		"updated_at":    gorm.Expr("updated_at"), // 防止 MySQL ON UPDATE CURRENT_TIMESTAMP 误刷新
 	}
 	return r.db.Model(&model.Post{}).Where("id = ?", postID).UpdateColumns(updates).Error
 }
@@ -258,6 +264,7 @@ func (r *PostRepository) Like(postID, userID string) error {
 			UpdateColumns(map[string]any{
 				"likes_count": gorm.Expr("likes_count + 1"),
 				"hot_score":   gorm.Expr("(likes_count + 1) * 2 + comments_count * 3 + views_count * 0.1"),
+				"updated_at":  gorm.Expr("updated_at"),
 			}).Error
 	})
 }
@@ -276,6 +283,7 @@ func (r *PostRepository) Unlike(postID, userID string) error {
 				UpdateColumns(map[string]any{
 					"likes_count": gorm.Expr("likes_count - 1"),
 					"hot_score":   gorm.Expr("(likes_count - 1) * 2 + comments_count * 3 + views_count * 0.1"),
+					"updated_at":  gorm.Expr("updated_at"),
 				}).Error
 		}
 		return nil
@@ -338,9 +346,12 @@ func (r *PostRepository) Favorite(postID, userID string) error {
 			return err
 		}
 
-		// 增加帖子收藏数
+		// 增加帖子收藏数（显式固定 updated_at，避免 MySQL ON UPDATE 误刷新）
 		return tx.Model(&model.Post{}).Where("id = ?", postID).
-			UpdateColumn("favorites_count", gorm.Expr("favorites_count + 1")).Error
+			UpdateColumns(map[string]any{
+				"favorites_count": gorm.Expr("favorites_count + 1"),
+				"updated_at":    gorm.Expr("updated_at"),
+			}).Error
 	})
 }
 
@@ -354,7 +365,10 @@ func (r *PostRepository) Unfavorite(postID, userID string) error {
 		if result.RowsAffected > 0 {
 			// 减少帖子收藏数
 			return tx.Model(&model.Post{}).Where("id = ?", postID).
-				UpdateColumn("favorites_count", gorm.Expr("favorites_count - 1")).Error
+				UpdateColumns(map[string]any{
+					"favorites_count": gorm.Expr("favorites_count - 1"),
+					"updated_at":    gorm.Expr("updated_at"),
+				}).Error
 		}
 		return nil
 	})
@@ -401,6 +415,7 @@ func (r *PostRepository) IncrementViews(postID string) error {
 		UpdateColumns(map[string]interface{}{
 			"views_count": gorm.Expr("views_count + 1"),
 			"hot_score":   gorm.Expr("likes_count * 2 + comments_count * 3 + (views_count + 1) * 0.1"),
+			"updated_at":  gorm.Expr("updated_at"),
 		}).Error
 }
 
@@ -537,7 +552,7 @@ func (r *PostRepository) createWithTx(tx *gorm.DB, post *model.Post, images []st
 		}
 	}
 
-	return nil
+	return tx.Model(post).Where("id = ?", post.ID).UpdateColumn("updated_at", post.CreatedAt).Error
 }
 
 // GetByIDWithContext 根据ID获取帖子（支持事务）
@@ -552,7 +567,9 @@ func (r *PostRepository) GetByIDWithContext(ctx context.Context, id string) (*mo
 
 // UpdateWithContext 更新帖子（支持事务）
 func (r *PostRepository) UpdateWithContext(ctx context.Context, post *model.Post) error {
-	post.UpdatedAt = time.Now()
+	now := time.Now()
+	post.UpdatedAt = now
+	post.ContentEditedAt = &now
 	return r.getDB(ctx).WithContext(ctx).Save(post).Error
 }
 
@@ -706,14 +723,20 @@ func (r *PostRepository) BatchUpdateStatus(ids []string, status model.PostStatus
 func (r *PostRepository) UpdatePinStatus(postID string, isPinned bool) error {
 	// 置顶状态属于管理操作，不应影响帖子内容更新时间（updated_at）
 	return r.db.Model(&model.Post{}).Where("id = ?", postID).
-		UpdateColumn("is_pinned", isPinned).Error
+		UpdateColumns(map[string]any{
+			"is_pinned":  isPinned,
+			"updated_at": gorm.Expr("updated_at"),
+		}).Error
 }
 
 // UpdateFeatureStatus 更新帖子加精状态
 func (r *PostRepository) UpdateFeatureStatus(postID string, isFeatured bool) error {
 	// 加精状态属于管理操作，不应影响帖子内容更新时间（updated_at）
 	return r.db.Model(&model.Post{}).Where("id = ?", postID).
-		UpdateColumn("is_featured", isFeatured).Error
+		UpdateColumns(map[string]any{
+			"is_featured": isFeatured,
+			"updated_at":  gorm.Expr("updated_at"),
+		}).Error
 }
 
 // ========== Cursor Pagination Methods ==========