TitleBarButton: Fix Foreground not using property value at initial

[seasonyuu]

Pull request type

Please check the type of change your PR introduces:

• Update
• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes

What is the current behavior?

Cause using RenderButtonsForeground as Canvas's FillColor, when app initial the window theme, ButtonsForeground changed but the event hadn't raised.

Issue Number: #1009 (comment)

What is the new behavior?

• Set RenderButtonsForeground as ButtonsForeground when TitleBarButton Loaded.

Other information

[DDarknessOne]

The problem is still present here.
Version: 3.0.3
OS: Windows 11 23H2

[seasonyuu]

The problem is still present here. Version: 3.0.3 OS: Windows 11 23H2

I had tried many times. Please show what you do.

[Abomariam1]

please write an example , the issue does not solved.

[DDarknessOne]

This it the unmodified WPF UI Gallery. The same thing happens when i create a blank net8.0 project with wpfui.

[seasonyuu]

I just run it from development branch without any change, it works like a charm.

@Abomariam1 @DDarknessOne , maybe you should clear build output dir and retry.

[seasonyuu]

PS, git log information.