Replaces WinUI 2 grey brushes with WinUI 3 equivalents and enables the Mica system backdrop on Windows 11. RootGrid is transparent when Mica is active so the material shows through; falls back to ApplicationPageBackgroundThemeBrush on Win10. Sensor header uses LayerFillColorDefaultBrush; plot pane border uses DividerStrokeColorDefaultBrush. Black theme keeps a solid background and disables Mica.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
JMR-devandCopilot
ac65b63a8f