feat(app): 初始化自动关机工具首个版本

实现基于 WPF 的 AutoShutdown 主界面，支持关机、重启、睡眠、休眠、唤醒、锁屏和注销等电源任务。

支持指定时间和倒计时计划、执行前提醒、系统关机撤销、Windows 唤醒任务、托盘运行、自定义图标以及 OmniNotify 通知适配。

修复关闭到托盘时的运行提醒，并支持单击托盘图标打开或收起主界面。

补充 README、发布配置和 win-x64 Release 输出要求。

Release: win-x64

Models/PowerAction.cs

@@ -0,0 +1,39 @@
+namespace AutoShutdown.Models;
+
+internal enum PowerAction
+{
+    Shutdown,
+    Restart,
+    Sleep,
+    Hibernate,
+    Wake,
+    Lock,
+    LogOff
+}
+
+internal static class PowerActionText
+{
+    public static string Label(this PowerAction action) => action switch
+    {
+        PowerAction.Shutdown => "关机",
+        PowerAction.Restart => "重启",
+        PowerAction.Sleep => "睡眠",
+        PowerAction.Hibernate => "休眠",
+        PowerAction.Wake => "唤醒",
+        PowerAction.Lock => "锁屏",
+        PowerAction.LogOff => "注销",
+        _ => action.ToString()
+    };
+
+    public static string Description(this PowerAction action) => action switch
+    {
+        PowerAction.Shutdown => "关闭电脑",
+        PowerAction.Restart => "重新启动电脑",
+        PowerAction.Sleep => "保留会话并进入低功耗状态",
+        PowerAction.Hibernate => "保存当前状态后断电待机",
+        PowerAction.Wake => "通过任务计划从睡眠或休眠中唤醒",
+        PowerAction.Lock => "锁定当前 Windows 会话",
+        PowerAction.LogOff => "注销当前用户",
+        _ => string.Empty
+    };
+}