AppWindowTitleBar caption button incorrect hover background color after toggling `Show accent on title bars and window borders`

### Describe the bug

WinUI3 caption button hover background color and glyph foreground color (when the window is inactive) does not listen to changes when toggling `Show accent on title bars and window borders`. It needs a restart to be correct again.

|case|UWP|WinUI3|
|--|--|--|
|In light mode, having it disbaled -> enabled|||
|In light mode, having it enabled -> disabled||

Dark mode is a similar situation, and I don't want to repeat it.

### Steps to reproduce the bug

See the table

### Expected behavior

_No response_

### Screenshots

_No response_

### NuGet package version

WinUI 3 - Windows App SDK 1.6.5: 1.6.250205002

### Windows version

Windows 11 (24H2): Build 26100

### Additional context

_No response_

Start by reproducing the issue in a WinUI 3 app on Windows 11 with Windows App SDK 1.6.5, then trace how AppWindowTitleBar caption button visual states respond to the accent setting toggle. Done means hover background and inactive-window glyph colors update correctly in both light and dark modes without restarting the app.

Written by the indexing model from the issue text.