* [Fonts] Add per-purpose font section to palette editor
* [Fonts] Make the editor's fallback and Reset preview-independent
- Add ThemeManager::defaultAppFont(), which resolves an unset role against the
startup font instead of currentFonts, and use it in FontGridWidget::loadFonts
so the grid never shows the live preview as the theme's default.
- Reload the live theme in PaletteEditorDialog::onReset before re-reading the
grid, so Reset restores the saved fonts before loadFonts resolves fallbacks.
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Co-authored-by: Lukas Brübach <Bruebach.Lukas@bdosecurity.de>