feat: 帖子全局/板块置顶支持权重排序，优化列表与详情渲染

service/post.go

@@ -813,11 +813,17 @@ func (s *PostService) Purge(postID uint) error {
 	})
 }
 
-func (s *PostService) SetPinned(postID uint, pinned bool) error {
+func (s *PostService) SetPinned(postID uint, pinned int) error {
+	if pinned < 0 {
+		pinned = 0
+	}
 	return model.DB.Model(&model.Post{}).Where("id = ?", postID).Update("pinned", pinned).Error
 }
 
-func (s *PostService) SetBoardPinned(postID uint, boardPinned bool) error {
+func (s *PostService) SetBoardPinned(postID uint, boardPinned int) error {
+	if boardPinned < 0 {
+		boardPinned = 0
+	}
 	return model.DB.Model(&model.Post{}).Where("id = ?", postID).Update("board_pinned", boardPinned).Error
 }