The dock background was a hardcoded dark fill because upstream
icon labels are white (for floating over wallpaper). Switching
to Theme.backgroundColor alone just made labels vanish on light
themes, so it kept getting reverted.
Fix the whole stack at once: background uses the Window color
set, hover highlights derive from Theme.textColor instead of
white, and delegate labels switch to Theme.textColor in
convergence mode (still white over wallpaper on mobile).
Qt.rgba expects 0.0–1.0 floats. Passing 255 for R/G/B saturates
every channel to 1.0, producing opaque white instead of the
intended semi-transparent tint. Fix all call sites across
FavouritesBar, StatusBar, and AbstractDelegate.
Dock buttons, running-app icons, and favourite delegates had no
mouse-over feedback. Add 3-state highlight backgrounds (hover
and press), Kirigami.Icon active state, and tooltips following
existing Plasma patterns. Favourite delegate hover is gated on
convergence mode to avoid overlap with touch press events.
