2.3.0：手表界面精简 + 播放器 + 鼠标重做

手表端
- 功能页从 10 个杂项精简到 7 个（屏幕/鼠标/媒体/文件/电脑/语音/电源）
- 删掉：游戏封锁、待办、掷骰子、抽奖、壁纸、显示器开关、定时关机、
  剪贴板历史、性能/磁盘/电量、文件夹浏览、教室限制等
- 改成显式列按钮，不再把电脑端所有功能组无脑铺到表盘
- 远程鼠标控制重做：滑动区 + 左键/滚轮/右键三按钮
  滚轮点按=中键、上下滑=滚动
- 新增视频/音乐播放器（手表本地播放）：进度拖动、左右滑快进退10秒、
  点画面播放暂停、上一/下一、播完自动下一首

电脑端
- 新增 kill_all（结束所有进程），白名单保护系统关键进程和自身
- 新增 media_list / media_pull（播放器数据源）
  安全边界：只允许媒体目录，用 relative_to 判断，防同前缀兄弟目录绕过

中转站
- known_devices 从 ID 集合改成「设备ID -> 配对码」映射
- 修复：管理员改码后关机超过 6 小时，改码会被超时清理冲掉
- 老格式 state 文件平滑升级

build/diag_tool/ykxmz诊断/warn-ykxmz诊断.txt

@@ -0,0 +1,25 @@
+
+This file lists modules PyInstaller was not able to find. This does not
+necessarily mean these modules are required for running your program. Both
+Python's standard library and 3rd-party Python packages often conditionally
+import optional modules, some of which may be available only on certain
+platforms.
+
+Types of import:
+* top-level: imported at the top-level - look at these first
+* conditional: imported within an if-statement
+* delayed: imported within a function
+* optional: imported within a try-except-statement
+
+IMPORTANT: Do NOT post this list to the issue-tracker. Use it as a basis for
+            tracking down the missing module yourself. Thanks!
+
+missing module named 'org.python' - imported by copy (optional)
+missing module named org - imported by pickle (optional)
+missing module named pwd - imported by posixpath (delayed, conditional), shutil (optional), tarfile (optional), pathlib (delayed, conditional, optional)
+missing module named grp - imported by shutil (optional), tarfile (optional), pathlib (delayed)
+missing module named _posixsubprocess - imported by subprocess (optional)
+missing module named _frozen_importlib_external - imported by importlib._bootstrap (delayed), importlib (optional), importlib.abc (optional)
+excluded module named _frozen_importlib - imported by importlib (optional), importlib.abc (optional)
+missing module named posix - imported by os (conditional, optional), shutil (conditional), importlib._bootstrap_external (conditional)
+missing module named resource - imported by posix (top-level)