feat: 公告系统 — Phase 2 完成

- Model/Repo/Service/Controller 全栈实现
- CRUD + ListActive（生效时间范围过滤）
- 管理后台独立页面 /admin/announcements（列表+弹窗CRUD）
- 前台首页 Hero 下方公告栏（info/success/warning/error 四色）
- Moderator+ 权限可管理公告

internal/router/admin.go

@@ -32,6 +32,7 @@ func setupAdminRoutes(r *gin.Engine, cfg *config.Config, d *dependencies) {
 		adminPages.GET("/energy/logs", d.adminEnergyCtrl.EnergyLogPage)
 		adminPages.GET("/energy/fund-logs", d.adminEnergyCtrl.FundLogPage)
 		adminPages.GET("/comments", d.adminCommentCtrl.CommentsPage)
+		adminPages.GET("/announcements", d.announcementCtrl.Page)
 	}
 
 	// --- 管理后台 API ---
@@ -99,4 +100,17 @@ func setupAdminRoutes(r *gin.Engine, cfg *config.Config, d *dependencies) {
 		adminCommentAPI.GET("", d.adminCommentCtrl.ListComments)
 		adminCommentAPI.DELETE("/:id", d.adminCommentCtrl.Delete)
 	}
+
+	// --- 公告管理 API（moderator+） ---
+	announcementAPI := r.Group("/api/admin/announcements")
+	announcementAPI.Use(d.authMdw.Required())
+	announcementAPI.Use(middleware.RequireMinRole(model.RoleModerator))
+	announcementAPI.Use(d.authMdw.BannedWriteGuard())
+	announcementAPI.Use(middleware.CSRF(cfg))
+	{
+		announcementAPI.GET("", d.announcementCtrl.List)
+		announcementAPI.POST("", d.announcementCtrl.Create)
+		announcementAPI.PUT("/:id", d.announcementCtrl.Update)
+		announcementAPI.DELETE("/:id", d.announcementCtrl.Delete)
+	}
 }

internal/router/deps_core.go

@@ -43,8 +43,10 @@ type dependencies struct {
 	followCtrl      *controller.FollowController
 	favoriteCtrl    *controller.FavoriteController
 	favoriteService *service.FavoriteService
-	trendsService   *service.TrendsService
-	homeCache       *cache.HomePageCache
+	trendsService     *service.TrendsService
+	homeCache         *cache.HomePageCache
+	announcementService *service.AnnouncementService
+	announcementCtrl    *adminCtrl.AnnouncementController
 }
 
 func buildDepsCore(db *gorm.DB, cfg *config.Config, siteSettings *config.SiteSettings, redisClient *redis.Client) (

internal/router/deps_extra.go

@@ -103,6 +103,11 @@ func buildDeps(db *gorm.DB, cfg *config.Config, siteSettings *config.SiteSetting
 
 	maintenanceMdw := middleware.NewMaintenanceMiddleware(cfg, siteSettings, sessionMgr)
 
+	// 公告系统
+	announcementRepo := repository.NewAnnouncementRepo(db)
+	announcementService := service.NewAnnouncementService(announcementRepo)
+	announcementCtrl := adminCtrl.NewAnnouncementController(announcementService)
+
 	// 首页内存缓存（30s TTL），文章变更时失效
 	homeCache := cache.NewHomePageCache(30 * time.Second)
 	postService.WithHomePageInvalidator(func() { homeCache.Invalidate() })
@@ -126,7 +131,9 @@ func buildDeps(db *gorm.DB, cfg *config.Config, siteSettings *config.SiteSetting
 		followCtrl:      followCtrl,
 		favoriteCtrl:    favoriteCtrl,
 		favoriteService: favoriteService,
-		trendsService:   trendsService,
-		homeCache:       homeCache,
+		trendsService:      trendsService,
+		homeCache:          homeCache,
+		announcementService: announcementService,
+		announcementCtrl:   announcementCtrl,
 	}
 }

internal/router/frontend.go

@@ -33,11 +33,13 @@ func setupFrontendRoutes(r *gin.Engine, cfg *config.Config, d *dependencies) {
 					d.homeCache.Set(posts, total)
 				}
 			}
+			announcements, _ := d.announcementService.ListActive()
 			c.HTML(http.StatusOK, "home/index.html", common.BuildPageData(c, gin.H{
-				"Title":     "首页",
-				"ExtraCSS":  "/static/css/home.css",
-				"Posts":     posts,
-				"PostCount": total,
+				"Title":         "首页",
+				"ExtraCSS":      "/static/css/home.css",
+				"Posts":         posts,
+				"PostCount":     total,
+				"Announcements": announcements,
 			}))
 		})