theme: GTK and Qt take the YoRHa palette

GTK moves from Catppuccin Mocha to adw-gtk3-dark, recoloured through the
libadwaita named colours in gtk-3.0/gtk.css and as CSS variables in
gtk-4.0/gtk.css, so Nautilus and other libadwaita apps follow too. The
gtk-4.0 symlinks into the Catppuccin theme are gone, since libadwaita
would load its gtk-dark.css over the overrides.

Qt gets qt6ct/colors/yorha.conf: the same palette in QPalette roles,
with the light slab as the highlight and ink as its text.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

qt6ct/colors/yorha.conf

@@ -0,0 +1,4 @@
+[ColorScheme]
+active_colors=#ffccd2cb, #ff20241f, #ff383e35, #ff2a2f28, #ff0c0d0b, #ff161915, #ffccd2cb, #ffeef1ea, #ffccd2cb, #ff0c0d0b, #ff0f110e, #ff090a08, #ffbcc1bf, #ff090a08, #ffeef1ea, #ff9fa7a2, #ff161915, #ff0f110e, #ff20241f, #ffccd2cb, #ff79847a, #ffbcc1bf
+inactive_colors=#ffccd2cb, #ff20241f, #ff383e35, #ff2a2f28, #ff0c0d0b, #ff161915, #ffccd2cb, #ffeef1ea, #ffccd2cb, #ff0c0d0b, #ff0f110e, #ff090a08, #ff383e35, #ffccd2cb, #ffeef1ea, #ff9fa7a2, #ff161915, #ff0f110e, #ff20241f, #ffccd2cb, #ff79847a, #ff383e35
+disabled_colors=#ff545c52, #ff161915, #ff2a2f28, #ff20241f, #ff0c0d0b, #ff161915, #ff545c52, #ff79847a, #ff545c52, #ff0c0d0b, #ff0f110e, #ff090a08, #ff20241f, #ff545c52, #ff79847a, #ff545c52, #ff161915, #ff0f110e, #ff20241f, #ff545c52, #ff464d44, #ff20241f