The color of the custom title bar close button is different from the system default title bar close button color

### Describe the bug

The color of the custom title bar close button is different from the system default title bar close button color

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自定义标题栏关闭按钮的颜色与系统默认的标题栏关闭按钮的颜色不一致

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WinUI 3 Custom title bar close button color, light red

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WinUI 3 自定义标题栏关闭按钮颜色，浅红色

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Explorer, Windows Terminal, Notepad Custom title bar, Control Panel default title bar close button color, dark red

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资源管理器，Windows 终端，记事本自定义标题栏，控制面板的默认标题栏关闭按钮颜色，深红色

### Steps to reproduce the bug

See description

### Expected behavior

The color of the WinUI 3 title bar close button is the same as that of the default title bar close button

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WinUI 3 标题栏关闭按钮的颜色与默认标题栏关闭按钮的颜色保持一致

### Screenshots

See description

### NuGet package version

WinUI 3 - Windows App SDK 1.6.3: 1.6.241114003

### Windows version

Windows 11 (23H2): Build 22631, Windows 11 (24H2): Build 26100, Windows 11 (22H2): Build 22621, Windows 11 (21H2): Build 22000, Windows 10 (21H2): Build 19044, Windows 10 (21H1): Build 19043, Windows 10 (20H2): Build 19042, Windows 10 (1809): Build 17763

### Additional context

None

Start by reproducing the close-button color difference in a WinUI 3 application using Windows App SDK 1.6.3 across the listed Windows versions, then inspect the custom title bar behavior against the system default. Done means the custom title bar close button matches the default title bar close-button color in the reported environments.

Written by the indexing model from the issue text.