功能：支持真实 2K 串流与重启持久化并优化渲染

变更详情：真2K串流与重启持久化，优化客户端渲染和帧率配置

三端统一2560x1440，盒子使用297MHz HDMI时序并保留1080p回退；Windows脚本动态定位VDD恢复2K。串流默认2K20/30Mbps，使用GLES2，设置页支持20/24FPS及自定义值。保持Windows正常光标，记录NVENC阶段性实测和GPU重启后Code43未恢复的限制。

tools/set-2k-display.ps1

@@ -0,0 +1,81 @@
+$ErrorActionPreference = 'Stop'
+Add-Type @'
+using System;
+using System.Runtime.InteropServices;
+public static class VdiDisplayMode {
+    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
+    public struct Device {
+        public int cb;
+        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)] public string Name;
+        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)] public string Description;
+        public int Flags;
+        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)] public string Id;
+        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)] public string Key;
+    }
+    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
+    public struct Mode {
+        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)] public string name;
+        public short spec, driver, size, extra;
+        public int fields, x, y, orientation, fixedOutput;
+        public short color, duplex, yres, tt, collate;
+        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 32)] public string form;
+        public short logPixels;
+        public int bpp, width, height, flags, hz, icmMethod, icmIntent, media, dither,
+            reserved1, reserved2, panWidth, panHeight;
+    }
+    [DllImport("user32.dll", CharSet = CharSet.Unicode)]
+    static extern bool EnumDisplayDevices(string name, uint index, ref Device dev, uint flags);
+    [DllImport("user32.dll", CharSet = CharSet.Unicode)]
+    static extern bool EnumDisplaySettings(string name, int index, ref Mode mode);
+    [DllImport("user32.dll", CharSet = CharSet.Unicode)]
+    static extern int ChangeDisplaySettingsEx(string name, ref Mode mode, IntPtr window, uint flags, IntPtr param);
+
+    public static string Find() {
+        for (uint i = 0; ; i++) {
+            var d = new Device();
+            d.cb = Marshal.SizeOf(typeof(Device));
+            if (!EnumDisplayDevices(null, i, ref d, 0)) return null;
+            if ((d.Flags & 1) != 0 && d.Description.IndexOf("Virtual Display Driver", StringComparison.OrdinalIgnoreCase) >= 0)
+                return d.Name;
+        }
+    }
+    public static string Current(string name) {
+        var m = new Mode();
+        m.size = (short)Marshal.SizeOf(typeof(Mode));
+        if (!EnumDisplaySettings(name, -1, ref m)) return "unavailable";
+        return m.width + "x" + m.height + "@" + m.hz;
+    }
+    public static int Apply(string name) {
+        for (int i = 0; ; i++) {
+            var m = new Mode();
+            m.size = (short)Marshal.SizeOf(typeof(Mode));
+            if (!EnumDisplaySettings(name, i, ref m)) return -99;
+            if (m.width == 2560 && m.height == 1440 && m.hz == 30) {
+                m.fields = 0x80000 | 0x100000 | 0x400000;
+                int test = ChangeDisplaySettingsEx(name, ref m, IntPtr.Zero, 2, IntPtr.Zero);
+                if (test != 0) return test;
+                return ChangeDisplaySettingsEx(name, ref m, IntPtr.Zero, 1, IntPtr.Zero);
+            }
+        }
+    }
+}
+'@
+$log = 'C:/ProgramData/VDI/set-2k-result.txt'
+try {
+    for ($i = 0; $i -lt 12; $i++) {
+        $dev = [VdiDisplayMode]::Find()
+        if ($dev) {
+            $result = [VdiDisplayMode]::Apply($dev)
+            $mode = [VdiDisplayMode]::Current($dev)
+            if ($result -eq 0 -and $mode -eq '2560x1440@30') {
+                "$(Get-Date -Format o) device=$dev result=0 mode=$mode" | Set-Content $log
+                exit 0
+            }
+        }
+        Start-Sleep 5
+    }
+    throw "2K mode not applied: device=$dev result=$result mode=$mode"
+} catch {
+    "$(Get-Date -Format o) ERROR $_" | Set-Content $log
+    exit 1
+}