feat(websocket): 优化投屏状态管理并新增全员禁麦功能

- 重构 Redis 投屏状态存储，统一使用 screenShareOwnerUid 字段
- 移除冗余的 screenShareUid 字段，简化房间状态数据结构
- 新增 client_mute_all_students 消息类型支持全员禁麦功能
- 实现创建者权限验证的全员禁麦逻辑，排除老师角色用户
- 优化 Tauri 桌面应用悬浮窗创建接口，支持状态参数传递
- 添加悬浮窗关闭功能及教师端静音状态同步机制
- 修复学生端界面中投屏状态变量命名不一致问题
- 统一按钮样式规范，提升界面组件一致性

node_api/src/modules/websocket/meeting-redis.service.ts

@@ -247,19 +247,14 @@ export class MeetingRedisService {
   /**
    * 设置投屏状态
    * @param roomId - 房间 ID
-   * @param screenShareUid - 投屏人短 UID，null 表示停止投屏
+   * @param screenShareOwnerUid - 投屏人短 UID，null 表示停止投屏
    */
-  async setScreenSharing(roomId: string, screenShareUid: number | null, screenShareOwnerUid?: number | null): Promise<void> {
+  async setScreenSharing(roomId: string, screenShareOwnerUid: number | null): Promise<void> {
     const key = `${this.KEY_PREFIX.ROOM_STATE}${roomId}`;
-    if (screenShareUid === null) {
-      await this.getClient().hdel(key, 'screenShareUid');
+    if (screenShareOwnerUid === null) {
       await this.getClient().hdel(key, 'screenShareOwnerUid');
     } else {
-      const hm: Record<string, string> = { screenShareUid: String(screenShareUid) };
-      if (typeof screenShareOwnerUid === 'number' && Number.isFinite(screenShareOwnerUid) && screenShareOwnerUid > 0) {
-        hm.screenShareOwnerUid = String(screenShareOwnerUid);
-      }
-      await this.getClient().hset(key, hm);
+      await this.getClient().hset(key, { screenShareOwnerUid: String(screenShareOwnerUid) });
       await this.getClient().expire(key, 24 * 60 * 60);
     }
   }
@@ -297,7 +292,6 @@ export class MeetingRedisService {
   async getRoomState(roomId: string): Promise<{
     classStatus: 'finished' | 'in_class' | 'not_started';
     speakerUid?: number;
-    screenShareUid?: number;
     screenShareOwnerUid?: number;
     teacherUid?: number;
     endTimestamp?: number;
@@ -306,14 +300,12 @@ export class MeetingRedisService {
     const map = await this.getClient().hgetall(key);
     const status = (map?.classStatus as any) || 'not_started';
     const speakerUid = map?.speakerUid ? Number(map.speakerUid) : undefined;
-    const screenShareUid = map?.screenShareUid ? Number(map.screenShareUid) : undefined;
     const screenShareOwnerUid = map?.screenShareOwnerUid ? Number(map.screenShareOwnerUid) : undefined;
     const teacherUid = map?.teacherUid ? Number(map.teacherUid) : undefined;
     const endTimestamp = map?.endTimestamp ? Number(map.endTimestamp) : undefined;
     return {
       classStatus: status,
       ...(Number.isFinite(speakerUid) ? { speakerUid } : {}),
-      ...(Number.isFinite(screenShareUid) ? { screenShareUid } : {}),
       ...(Number.isFinite(screenShareOwnerUid) ? { screenShareOwnerUid } : {}),
       ...(Number.isFinite(teacherUid) ? { teacherUid } : {}),
       ...(Number.isFinite(endTimestamp) ? { endTimestamp } : {}),