feat: Studio 概览/分析补上阅读量 + 详情页 meta 行改版

- StudioOverview 新增 TotalViews 字段，GetOverviewByUserID 查询含 SUM(views_count)
- 新增 ViewTrendStore 接口和 AggregateViewsByAuthor，UNION ALL 合并已登录+访客阅读日志按日期聚合
- 数据分析页面新增阅读量趋势折线图（绿色，Chart.js）
- 概览和数据分析页面新增总阅读量统计卡片
- 详情页 meta 行改为标签格式：作者/阅读/点赞/收藏/评论/发布时间
- 移除详情页公开状态徽章，已锁定+理由仅作者可见

internal/repository/post_stats_repo.go

@@ -4,6 +4,7 @@ import (
 	"time"
 
 	"metazone.cc/metalab/internal/model"
+	"metazone.cc/metalab/internal/service"
 
 	"gorm.io/gorm"
 	"gorm.io/gorm/clause"
@@ -40,10 +41,11 @@ type overviewRow struct {
 	PendingCount  int64
 	ApprovedCount int64
 	RejectedCount int64
+	TotalViews    int64
 }
 
-// GetOverviewByUserID 用单次 GROUP BY 查询聚合用户各状态文章数
-func (r *PostRepo) GetOverviewByUserID(userID uint) (totalPosts, draftCount, pendingCount, approvedCount, rejectedCount int64, err error) {
+// GetOverviewByUserID 用单次 GROUP BY 查询聚合用户各状态文章数 + 总阅读量
+func (r *PostRepo) GetOverviewByUserID(userID uint) (totalPosts, draftCount, pendingCount, approvedCount, rejectedCount, totalViews int64, err error) {
 	var row overviewRow
 	err = r.db.Model(&model.Post{}).
 		Select(`
@@ -51,11 +53,12 @@ func (r *PostRepo) GetOverviewByUserID(userID uint) (totalPosts, draftCount, pen
 			COALESCE(SUM(CASE WHEN status = 'draft' THEN 1 ELSE 0 END), 0) AS draft_count,
 			COALESCE(SUM(CASE WHEN status = 'pending' THEN 1 ELSE 0 END), 0) AS pending_count,
 			COALESCE(SUM(CASE WHEN status = 'approved' THEN 1 ELSE 0 END), 0) AS approved_count,
-			COALESCE(SUM(CASE WHEN status = 'rejected' THEN 1 ELSE 0 END), 0) AS rejected_count
+			COALESCE(SUM(CASE WHEN status = 'rejected' THEN 1 ELSE 0 END), 0) AS rejected_count,
+			COALESCE(SUM(views_count), 0) AS total_views
 		`).
 		Where("user_id = ? AND deleted_at IS NULL", userID).
 		Scan(&row).Error
-	return row.TotalPosts, row.DraftCount, row.PendingCount, row.ApprovedCount, row.RejectedCount, err
+	return row.TotalPosts, row.DraftCount, row.PendingCount, row.ApprovedCount, row.RejectedCount, row.TotalViews, err
 }
 
 // readCooldown 两次阅读记录最小间隔
@@ -106,3 +109,26 @@ func (r *PostRepo) IncrementViewsCount(postID uint) error {
 	return r.db.Model(&model.Post{}).Where("id = ?", postID).
 		Update("views_count", gorm.Expr("views_count + 1")).Error
 }
+
+// AggregateViewsByAuthor 按日期聚合阅读量（作者所有文章在时间段内的阅读记录，含已登录+访客）
+func (r *PostRepo) AggregateViewsByAuthor(userID uint, since string) ([]service.TrendPoint, error) {
+	var results []service.TrendPoint
+	err := r.db.Raw(`
+		SELECT TO_CHAR(t.read_at, 'YYYY-MM-DD') AS date, COUNT(*) AS value
+		FROM (
+			SELECT prl.read_at FROM post_read_logs prl
+			JOIN posts p ON p.id = prl.post_id
+			WHERE p.user_id = ? AND prl.read_at >= ?
+			UNION ALL
+			SELECT pgrl.read_at FROM post_guest_read_logs pgrl
+			JOIN posts p ON p.id = pgrl.post_id
+			WHERE p.user_id = ? AND pgrl.read_at >= ?
+		) t
+		GROUP BY TO_CHAR(t.read_at, 'YYYY-MM-DD')
+		ORDER BY date ASC
+	`, userID, since, userID, since).Scan(&results).Error
+	if results == nil {
+		results = []service.TrendPoint{}
+	}
+	return results, err
+}