[VisualStylesMode: Net11] CheckBox glyph and Button border rendering appears blurry in VisualStylesMode.Net11

### .NET version

.NET 11.0.100-preview.7.26365.114 + Private dlls built from Net11/Integration-2 branch of https://github.com/KlausLoeffelmann/winforms repo

### Did it work in .NET Framework?

Yes

### Did it work in any of the earlier releases of .NET Core or .NET 5+?

Not support, new feature

### Issue description

When a CheckBox control is configured with: `checkBox1.FlatStyle = FlatStyle.Popup;`, Form's VisualStylesMode is set as VisualStylesMode.Net11,
the checkbox glyph (the square check box indicator) appears blurry, overly bold, or visually unclear.
Compared to the rendering in other visual style modes, the glyph loses sharpness and appears thicker than expected, resulting in a degraded visual appearance.
Also, button border has the similar issue.

### Steps to reproduce

1. Create a WinForms application targeting .NET 11 Preview
2. Configure Form's VisualStylesMode = VisualStylesMode.Net11
3. Add a CheckBox control to a form, and set `checkBox1.FlatStyle = FlatStyle.Popup`
4. Run the application

Start by reproducing the issue in a .NET 11 Preview WinForms application with VisualStylesMode.Net11 and a Popup CheckBox, then compare the CheckBox glyph and Button border rendering with other visual style modes. Done means both elements render sharply without the reported blur or excessive boldness.

Written by the indexing model from the issue text.