feat: Qt6 Sensors + KWin real build attempt, unblock kf6-kcmutils

- Qt6::Sensors v6.11.0 builds on Redox with dummy backend (520KB pkgar)
- KWin: now attempts real cmake build (KWIN_BUILD_X11/KCMS/
  SCREENLOCKER/TABBOX/GLOBALSHORTCUTS/RUNNERS/NOTIFICATIONS=OFF)
  with fallback to redbear-compositor wrapper on cmake failure
- kf6-kcmutils and kdecoration enabled in config (now have pkgar)
- KWin dependencies: qt6-sensors, libepoxy-stub, libudev-stub,
  kf6-kwayland, kf6-kwindowsystem, plasma-wayland-protocols
- Remaining KWin blockers: libinput (ignored), QML/Quick (JIT off)

config/redbear-full.toml

@@ -57,12 +57,12 @@ qt6-sensors = {}
 kf6-kio = {}
 # kde-cli-tools = {}   # blocked: direct repo cook fails
 
-# kdecoration = {}  # blocked: no pkgar artifact in repo
+kdecoration = {}
 kf6-attica = {}
 kf6-karchive = {}
 kf6-kauth = {}
 kf6-kbookmarks = {}
-# kf6-kcmutils = {}  # blocked: no pkgar artifact in repo
+kf6-kcmutils = {}
 kf6-kcodecs = {}
 kf6-kcolorscheme = {}
 kf6-kcompletion = {}