feat: 完成社区首页功能迭代，新增首页聚合与工作台组件

本次提交实现了完整的社区首页功能：
1. 新增首页聚合接口与服务，包含社区统计、热门帖、活跃用户与板块数据
2. 实现帖子推荐排序、SSR缓存与点赞态同步逻辑
3. 重构导航与布局系统，新增工作台侧边栏与移动端适配
4. 优化主题色与UI样式，统一设计系统风格
5. 修复登录注册页自动跳转与组件状态同步问题

backend/handler/handlers.go

@@ -14,4 +14,5 @@ type Handlers struct {
 	Comment      *service.CommentService
 	Like         *service.LikeService
 	Notification *service.NotificationService
+	OverviewSvc  *service.OverviewService
 }

backend/handler/overview.go

@@ -0,0 +1,34 @@
+package handler
+
+import (
+	"net/http"
+
+	"github.com/freefire/jiang13-bbs/middleware"
+	"github.com/gin-gonic/gin"
+)
+
+// Overview 首页聚合数据：统计、热门榜、活跃用户、板块计数
+func (h *Handlers) Overview(c *gin.Context) {
+	data, err := h.OverviewSvc.Get()
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
+		return
+	}
+	// 热门榜按当前登录用户填充点赞态
+	if claims := middleware.CurrentUser(c); claims != nil {
+		ids := make([]uint, 0, len(data.Hot))
+		for _, p := range data.Hot {
+			ids = append(ids, p.ID)
+		}
+		likedMap := h.Like.BatchHasLiked(ids, claims.ID)
+		for i := range data.Hot {
+			data.Hot[i].Liked = likedMap[data.Hot[i].ID]
+		}
+	}
+	c.JSON(http.StatusOK, gin.H{
+		"stats":        data.Stats,
+		"hot":          data.Hot,
+		"active_users": data.ActiveUsers,
+		"boards":       data.Boards,
+	})
+}

backend/handler/post.go

@@ -16,13 +16,15 @@ func (h *Handlers) Posts(c *gin.Context) {
 	boardID, _ := strconv.ParseUint(c.Query("board_id"), 10, 64)
 	sort := c.DefaultQuery("sort", "latest")
 	keyword := c.Query("keyword")
+	recommended := c.Query("recommended") == "true"
 
 	items, total, err := h.Post.List(service.PostListQuery{
-		BoardID: uint(boardID),
-		Page:    page,
-		Size:    size,
-		Sort:    sort,
-		Keyword: keyword,
+		BoardID:     uint(boardID),
+		Page:        page,
+		Size:        size,
+		Sort:        sort,
+		Keyword:     keyword,
+		Recommended: recommended,
 	})
 	if err != nil {
 		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})