Adds OutlinedLabel, a small QLabel subclass that paints each character
with a colored outline and a hollow interior. Used for the HD badge
in the status bar so each letter H and D is bordered in the same
- outline + fill done in custom paintEvent (no QSS hacks)
- updateHDStatus() now drives setOutlineColor/setOutlineWidth
directly instead of stylesheets
- registered OutlinedLabel as a custom widget in mainwindow.ui
- labelHdIcon pointer type updated to OutlinedLabel*
Krystie