feat(moderation): 帖评删除占位感知与硬删清场

管理删帖须填类型与理由并展示专用页；评论软删占位、版主可硬删不占楼。

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/handler/moderation.go

@@ -6,6 +6,7 @@ import (
 	"strconv"
 
 	"github.com/freefire/jiang13-bbs/middleware"
+	"github.com/freefire/jiang13-bbs/model"
 	"github.com/freefire/jiang13-bbs/service"
 	"github.com/gin-gonic/gin"
 	"gorm.io/gorm"
@@ -118,7 +119,33 @@ func (h *Handlers) AdminListComments(c *gin.Context) {
 }
 
 func (h *Handlers) AdminSoftDeletePost(c *gin.Context) {
-	h.execContentAction(c, h.Moderation.SoftDeletePost)
+	id, err := strconv.ParseUint(c.Param("id"), 10, 64)
+	if err != nil || id == 0 {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "无效的 ID"})
+		return
+	}
+	var body struct {
+		DeleteType   string `json:"delete_type"`
+		DeleteReason string `json:"delete_reason"`
+	}
+	if err := c.ShouldBindJSON(&body); err != nil {
+		c.JSON(http.StatusBadRequest, gin.H{"error": "请提交删除类型与理由"})
+		return
+	}
+	actor := middleware.CurrentActor(c)
+	authorID, err := h.Moderation.SoftDeletePost(actor, uint(id), body.DeleteType, body.DeleteReason)
+	if err != nil {
+		h.writeModerationError(c, err)
+		return
+	}
+	label := model.PostDeleteTypeLabel(body.DeleteType)
+	preview := label
+	if body.DeleteReason != "" {
+		preview = label + "：" + body.DeleteReason
+	}
+	h.Notification.Create(authorID, actor.ID, model.NotificationTypeDeleted, uint(id), 0, preview)
+	h.broadcastModerationChanged()
+	c.JSON(http.StatusOK, gin.H{"message": "操作成功"})
 }
 
 func (h *Handlers) AdminRestorePost(c *gin.Context) {
@@ -168,7 +195,9 @@ func (h *Handlers) writeModerationError(c *gin.Context, err error) {
 	default:
 		msg := err.Error()
 		if msg == "帖子已在回收站" || msg == "帖子未被删除" ||
-			msg == "评论已在回收站" || msg == "评论未被删除" {
+			msg == "评论已在回收站" || msg == "评论未被删除" ||
+			msg == "无效的删除类型" || msg == "请填写删除理由" ||
+			msg == "删除理由不能超过 200 字" {
 			c.JSON(http.StatusBadRequest, gin.H{"error": msg})
 			return
 		}