feat(announcements,messaging,notifications): 实现所有长期问题 — SSE 实时推送 + 通知日志持久化 + 优先级/归档 + 消息星标/草稿 + 公告已读回执/置顶 + 分类筛选/桌面推送 + 测试覆盖

P1-8 通知实时推送（SSE）:
- 新增 /api/notifications/stream SSE 端点（15 秒推送，5 分钟超时）
- 新增 useNotificationStream Hook（SSE + 轮询降级）
- NotificationDropdown 改用 SSE 实时推送

P2-12 测试覆盖:
- notifications/dispatcher.test.ts（6 个测试，渠道选择逻辑）
- notifications/channels/in-app-channel.test.ts（9 个测试，类型映射）
- messaging/schema.test.ts（34 个测试，Zod 校验）
- tests/e2e/messages.spec.ts（消息模块 E2E 测试）
- vitest.unit.config.ts 添加 server-only stub

P2-13a 通知发送日志持久化:
- 新增 notification_logs 表（userId/title/channel/status/messageId/error/sentAt）
- logNotificationSend 改为 async 写入 DB（失败降级 console）
- dispatcher 传递 payload 用于持久化

P2-13b 通知优先级和归档:
- messageNotifications 表新增 priority（low/normal/high/urgent）和 isArchived 字段
- getNotifications 支持归档和优先级筛选
- 新增 archiveNotificationAction
- NotificationList 显示优先级 Badge 和归档按钮

P2-13c 消息星标和草稿:
- messages 表新增 isStarred 字段
- 新增 message_drafts 表
- 新增 toggleMessageStar + 草稿 CRUD Server Actions
- 新增 5 个草稿 data-access 函数

P2-13d 公告已读回执和置顶:
- announcements 表新增 isPinned 字段
- 新增 announcement_reads 表（唯一索引保证幂等）
- 新增 toggleAnnouncementPinAction + markAnnouncementAsReadAction
- getAnnouncements 排序置顶优先

P2-13e 通知分类筛选和桌面推送:
- NotificationList 添加按类型筛选按钮组
- 新增 useDesktopNotifications Hook（浏览器 Notification API）
- NotificationDropdown 集成桌面推送（新通知触发）

架构图同步:
- 004 和 005 均已更新（新增表、Action、Hook、组件描述）

docs/architecture/005_architecture_data.json

@@ -8408,6 +8408,45 @@
             "usedBy": [
               "待扩展"
             ]
+          },
+          {
+            "name": "toggleAnnouncementPinAction",
+            "permission": "ANNOUNCEMENT_MANAGE",
+            "signature": "(id: string) => Promise<ActionState<string>>",
+            "purpose": "V2-P2-13d 新增：切换公告置顶状态（置顶公告在列表中优先显示）",
+            "deps": [
+              "requirePermission",
+              "data-access.toggleAnnouncementPin"
+            ],
+            "usedBy": [
+              "待扩展"
+            ]
+          },
+          {
+            "name": "markAnnouncementAsReadAction",
+            "permission": "ANNOUNCEMENT_READ",
+            "signature": "(announcementId: string) => Promise<ActionState<string>>",
+            "purpose": "V2-P2-13d 新增：标记公告为已读（当前用户维度，幂等）",
+            "deps": [
+              "requirePermission",
+              "data-access.markAnnouncementAsRead"
+            ],
+            "usedBy": [
+              "待扩展"
+            ]
+          },
+          {
+            "name": "getAnnouncementReadStatusAction",
+            "permission": "ANNOUNCEMENT_READ",
+            "signature": "(announcementIds: string[]) => Promise<ActionState<Record<string, boolean>>>",
+            "purpose": "V2-P2-13d 新增：批量获取当前用户对多个公告的已读状态（用于列表页标记已读/未读）",
+            "deps": [
+              "requirePermission",
+              "data-access.getAnnouncementReadStatusForUser"
+            ],
+            "usedBy": [
+              "待扩展"
+            ]
           }
         ],
         "dataAccess": [
@@ -8505,6 +8544,71 @@
             "usedBy": [
               "archiveAnnouncementAction"
             ]
+          },
+          {
+            "name": "toggleAnnouncementPin",
+            "signature": "(id: string) => Promise<void>",
+            "file": "data-access.ts",
+            "purpose": "V2-P2-13d 新增：切换公告置顶状态（查询当前 isPinned 后取反更新）",
+            "deps": [
+              "shared.db",
+              "shared.db.schema.announcements"
+            ],
+            "usedBy": [
+              "toggleAnnouncementPinAction"
+            ]
+          },
+          {
+            "name": "markAnnouncementAsRead",
+            "signature": "(announcementId: string, userId: string) => Promise<void>",
+            "file": "data-access.ts",
+            "purpose": "V2-P2-13d 新增：标记公告为已读（先查后插，依赖唯一索引保证幂等）",
+            "deps": [
+              "shared.db",
+              "shared.db.schema.announcementReads"
+            ],
+            "usedBy": [
+              "markAnnouncementAsReadAction"
+            ]
+          },
+          {
+            "name": "isAnnouncementReadByUser",
+            "signature": "(announcementId: string, userId: string) => Promise<boolean>",
+            "file": "data-access.ts",
+            "purpose": "V2-P2-13d 新增：检查用户是否已读指定公告",
+            "deps": [
+              "shared.db",
+              "shared.db.schema.announcementReads"
+            ],
+            "usedBy": [
+              "待扩展"
+            ]
+          },
+          {
+            "name": "getAnnouncementReadCount",
+            "signature": "(announcementId: string) => Promise<number>",
+            "file": "data-access.ts",
+            "purpose": "V2-P2-13d 新增：获取公告的已读用户数（管理端统计）",
+            "deps": [
+              "shared.db",
+              "shared.db.schema.announcementReads"
+            ],
+            "usedBy": [
+              "待扩展"
+            ]
+          },
+          {
+            "name": "getAnnouncementReadStatusForUser",
+            "signature": "(announcementIds: string[], userId: string) => Promise<Map<string, boolean>>",
+            "file": "data-access.ts",
+            "purpose": "V2-P2-13d 新增：批量获取用户对多个公告的已读状态（列表页标记已读/未读）",
+            "deps": [
+              "shared.db",
+              "shared.db.schema.announcementReads"
+            ],
+            "usedBy": [
+              "getAnnouncementReadStatusAction"
+            ]
           }
         ],
         "schemas": [
@@ -8532,7 +8636,7 @@
             "name": "Announcement",
             "type": "interface",
             "file": "types.ts",
-            "definition": "{ id, title, content, type, status, targetGradeId, targetClassId, authorId, authorName, publishedAt, createdAt, updatedAt }",
+            "definition": "{ id, title, content, type, status, targetGradeId, targetClassId, authorId, authorName, publishedAt, isPinned, isReadByCurrentUser?, readCount?, createdAt, updatedAt }",
             "usedBy": [
               "announcements/components",
               "页面"
@@ -8576,6 +8680,15 @@
               "getAnnouncements",
               "getAnnouncementsAction"
             ]
+          },
+          {
+            "name": "AnnouncementRead",
+            "type": "interface",
+            "file": "types.ts",
+            "definition": "{ id, announcementId, userId, readAt }",
+            "usedBy": [
+              "data-access.announcement_reads 相关函数"
+            ]
           }
         ],
         "components": [
@@ -10820,6 +10933,64 @@
               "unread-message-badge.tsx"
             ]
           },
+          {
+            "name": "toggleMessageStarAction",
+            "permission": "MESSAGE_READ",
+            "signature": "(messageId: string) => Promise<ActionState<string>>",
+            "purpose": "V2-P2-13c 新增：切换消息星标状态（仅接收方可标记；trackEvent 埋点 message.star_toggled）",
+            "deps": [
+              "requirePermission",
+              "schema.MessageIdSchema",
+              "data-access.toggleMessageStar",
+              "trackEvent",
+              "revalidatePath"
+            ],
+            "usedBy": [
+              "message-detail.tsx",
+              "message-list.tsx"
+            ]
+          },
+          {
+            "name": "getMessageDraftsAction",
+            "permission": "MESSAGE_SEND",
+            "signature": "() => Promise<ActionState<MessageDraft[]>>",
+            "purpose": "V2-P2-13c 新增：获取当前用户的消息草稿列表（按 updatedAt 倒序）",
+            "deps": [
+              "requirePermission",
+              "data-access.getMessageDrafts"
+            ],
+            "usedBy": [
+              "messages/compose/page.tsx"
+            ]
+          },
+          {
+            "name": "saveMessageDraftAction",
+            "permission": "MESSAGE_SEND",
+            "signature": "(prevState: ActionState<string> | null, formData: FormData) => Promise<ActionState<string>>",
+            "purpose": "V2-P2-13c 新增：保存消息草稿（FormData 含 draftId 时更新，否则创建新草稿；返回草稿 ID）",
+            "deps": [
+              "requirePermission",
+              "data-access.createMessageDraft",
+              "data-access.updateMessageDraft"
+            ],
+            "usedBy": [
+              "messages/compose/page.tsx"
+            ]
+          },
+          {
+            "name": "deleteMessageDraftAction",
+            "permission": "MESSAGE_SEND",
+            "signature": "(draftId: string) => Promise<ActionState<string>>",
+            "purpose": "V2-P2-13c 新增：删除消息草稿（仅草稿所有者可删；revalidatePath /messages/compose）",
+            "deps": [
+              "requirePermission",
+              "data-access.deleteMessageDraft",
+              "revalidatePath"
+            ],
+            "usedBy": [
+              "messages/compose/page.tsx"
+            ]
+          },
           {
             "name": "getNotificationPreferencesAction",
             "permission": "MESSAGE_READ",
@@ -10929,6 +11100,19 @@
               "deleteMessageAction"
             ]
           },
+          {
+            "name": "toggleMessageStar",
+            "signature": "(id: string, userId: string) => Promise<void>",
+            "file": "data-access.ts",
+            "purpose": "V2-P2-13c 新增：切换消息星标状态（仅接收方可标记；查询当前 isStarred 后取反更新）",
+            "deps": [
+              "shared.db",
+              "shared.db.schema.messages"
+            ],
+            "usedBy": [
+              "toggleMessageStarAction"
+            ]
+          },
           {
             "name": "getUnreadMessageCount",
             "signature": "(userId: string) => Promise<number>",
@@ -10987,6 +11171,74 @@
               "getRecipientsAction",
               "messages/compose/page.tsx"
             ]
+          },
+          {
+            "name": "getMessageDrafts",
+            "signature": "(userId: string) => Promise<MessageDraft[]>",
+            "file": "data-access.ts",
+            "purpose": "V2-P2-13c 新增：获取用户消息草稿列表（按 updatedAt 倒序；React cache 包装；批量解析 receiverName）",
+            "deps": [
+              "shared.db",
+              "shared.db.schema.messageDrafts",
+              "shared.db.schema.users"
+            ],
+            "usedBy": [
+              "getMessageDraftsAction"
+            ]
+          },
+          {
+            "name": "createMessageDraft",
+            "signature": "(data: CreateMessageDraftInput) => Promise<string>",
+            "file": "data-access.ts",
+            "purpose": "V2-P2-13c 新增：创建消息草稿（cuid2 生成 ID；返回新草稿 ID）",
+            "deps": [
+              "shared.db",
+              "shared.db.schema.messageDrafts",
+              "@paralleldrive/cuid2"
+            ],
+            "usedBy": [
+              "saveMessageDraftAction"
+            ]
+          },
+          {
+            "name": "updateMessageDraft",
+            "signature": "(id: string, userId: string, data: UpdateMessageDraftInput) => Promise<void>",
+            "file": "data-access.ts",
+            "purpose": "V2-P2-13c 新增：更新消息草稿（仅 owner 可改；未提供字段保留原值；updatedAt 由 onUpdateNow 自动更新）",
+            "deps": [
+              "shared.db",
+              "shared.db.schema.messageDrafts"
+            ],
+            "usedBy": [
+              "saveMessageDraftAction"
+            ]
+          },
+          {
+            "name": "deleteMessageDraft",
+            "signature": "(id: string, userId: string) => Promise<void>",
+            "file": "data-access.ts",
+            "purpose": "V2-P2-13c 新增：删除消息草稿（仅 owner 可删）",
+            "deps": [
+              "shared.db",
+              "shared.db.schema.messageDrafts"
+            ],
+            "usedBy": [
+              "deleteMessageDraftAction"
+            ]
+          },
+          {
+            "name": "getMessageDraftById",
+            "signature": "(id: string, userId: string) => Promise<MessageDraft | null>",
+            "file": "data-access.ts",
+            "purpose": "V2-P2-13c 新增：按 ID 获取单条消息草稿（仅 owner 可读；解析 receiverName）",
+            "deps": [
+              "shared.db",
+              "shared.db.schema.messageDrafts",
+              "shared.db.schema.users"
+            ],
+            "usedBy": [
+              "messages/compose/page.tsx"
+            ]
           }
         ],
         "notificationPreferences": [
@@ -11032,7 +11284,7 @@
             "name": "Message",
             "type": "type",
             "file": "types.ts",
-            "definition": "{ id, senderId, receiverId, subject: string | null, content, isRead, readAt: string | null, parentMessageId: string | null, createdAt, senderName, receiverName }",
+            "definition": "{ id, senderId, receiverId, subject: string | null, content, isRead, isStarred, readAt: string | null, parentMessageId: string | null, createdAt, senderName, receiverName }",
             "usedBy": [
               "messaging/components",
               "页面"
@@ -11121,6 +11373,36 @@
               "compose 页面下拉选项"
             ]
           },
+          {
+            "name": "MessageDraft",
+            "type": "type",
+            "file": "types.ts",
+            "definition": "V2-P2-13c 新增：{ id, userId, receiverId: string | null, receiverName: string | null, subject: string | null, content: string | null, parentMessageId: string | null, createdAt, updatedAt }",
+            "usedBy": [
+              "getMessageDrafts",
+              "getMessageDraftById",
+              "getMessageDraftsAction",
+              "messages/compose/page.tsx"
+            ]
+          },
+          {
+            "name": "CreateMessageDraftInput",
+            "type": "type",
+            "file": "types.ts",
+            "definition": "V2-P2-13c 新增：{ userId, receiverId?, subject?, content?, parentMessageId? }",
+            "usedBy": [
+              "createMessageDraft"
+            ]
+          },
+          {
+            "name": "UpdateMessageDraftInput",
+            "type": "type",
+            "file": "types.ts",
+            "definition": "V2-P2-13c 新增：{ receiverId?, subject?, content?, parentMessageId? }（未提供字段保留原值）",
+            "usedBy": [
+              "updateMessageDraft"
+            ]
+          },
           {
             "name": "PaginatedResult",
             "type": "type",
@@ -11705,12 +11987,30 @@
           {
             "name": "NotificationList",
             "file": "components/notification-list.tsx",
-            "purpose": "P1-4 新增（从 messaging 迁移）：通知完整列表（全部标记已读、单条标记已读、查看链接）；V2-P0-1 优化：useTranslations 命名空间从 'messages' 切换到独立的 'notifications'"
+            "purpose": "P1-4 新增（从 messaging 迁移）：通知完整列表（全部标记已读、单条标记已读、查看链接）；V2-P0-1 优化：useTranslations 命名空间从 'messages' 切换到独立的 'notifications'；V2-P2-13b：支持优先级 Badge 显示和归档操作；V2-P2-13c：支持按类型筛选（all/message/announcement/homework/grade）+ 空状态区分'无通知'/'无筛选结果'"
           },
           {
             "name": "NotificationDropdown",
             "file": "components/notification-dropdown.tsx",
-            "purpose": "P1-4 新增（从 messaging 迁移）：SiteHeader 通知下拉菜单（Bell 图标 + 未读数 Badge，每 30 秒轮询，滚动列表，标记已读，查看全部链接）；V2-P0-1 优化：useTranslations 命名空间从 'messages' 切换到独立的 'notifications'；V2-P2-1 优化：轮询间隔提取为 POLL_INTERVAL_MS 常量"
+            "purpose": "P1-4 新增（从 messaging 迁移）：SiteHeader 通知下拉菜单（Bell 图标 + 未读数 Badge，每 30 秒轮询，滚动列表，标记已读，查看全部链接）；V2-P0-1 优化：useTranslations 命名空间从 'messages' 切换到独立的 'notifications'；V2-P2-1 优化：轮询间隔提取为 POLL_INTERVAL_MS 常量；V2-P3：改用 SSE 实时推送 + 轮询降级；V2-P2-13c：集成 useDesktopNotifications 桌面推送，监听新通知并触发桌面提醒（首次加载不批量推送）"
+          }
+        ],
+        "hooks": [
+          {
+            "name": "useNotificationStream",
+            "file": "hooks/use-notification-stream.ts",
+            "purpose": "V2-P3 新增：SSE 实时推送 Hook（EventSource + 轮询降级），管理 SSE 连接生命周期，降级时通过 pollFnRef 调用 Server Actions 轮询",
+            "usedBy": [
+              "components/notification-dropdown.tsx"
+            ]
+          },
+          {
+            "name": "useDesktopNotifications",
+            "file": "hooks/use-desktop-notifications.ts",
+            "purpose": "V2-P2-13c 新增：浏览器桌面推送 Hook（Notification API），支持权限管理、自动请求权限、新通知桌面推送、点击跳转回调；SSR 安全（typeof window !== 'undefined' 检查）",
+            "usedBy": [
+              "components/notification-dropdown.tsx"
+            ]
           }
         ]
       }
@@ -14956,7 +15256,7 @@
   },
   "dbTables": {
     "_meta": {
-      "total": 59,
+      "total": 60,
       "orm": "Drizzle ORM 0.45",
       "database": "MySQL",
       "idStrategy": "CUID2 (varchar length 128)",
@@ -15152,7 +15452,11 @@
       "tables": {
         "announcements": {
           "owner": "announcements",
-          "description": "公告(school/grade/class,draft/published/archived)"
+          "description": "公告(school/grade/class,draft/published/archived;V2-P2-13d 新增 isPinned 置顶字段)"
+        },
+        "announcementReads": {
+          "owner": "announcements",
+          "description": "公告已读回执(V2-P2-13d 新增,唯一索引 announcementId+userId 保证幂等,cascade 删除)"
         }
       }
     },
@@ -15209,7 +15513,11 @@
       "tables": {
         "messages": {
           "owner": "messaging",
-          "description": "站内消息(含回复链 parentMessageId；软删除 senderDeletedAt/receiverDeletedAt)"
+          "description": "站内消息(含回复链 parentMessageId；软删除 senderDeletedAt/receiverDeletedAt；V2-P2-13c 新增 isStarred 星标字段 + messages_receiver_starred_idx 复合索引)"
+        },
+        "messageDrafts": {
+          "owner": "messaging",
+          "description": "V2-P2-13c 新增：消息草稿(userId/receiverId/subject/content/parentMessageId + updatedAt/createdAt；含 message_drafts_user_idx 和 message_drafts_user_updated_idx 索引)"
         },
         "messageNotifications": {
           "owner": "notifications",
@@ -15841,6 +16149,7 @@
           "auth-guard.requirePermission",
           "auth-guard.requireAuth",
           "db.schema.announcements",
+          "db.schema.announcementReads",
           "types.permissions"
         ],
         "auth": [