feat(l1): L2 splash, hovering Home icons, soft selections, two-line DM bubbles

- Splash: the L2 wordmark and lettering, shared through ui-core/Lettering.h,
  rise in with loading dots under the version line (static frame on e-ink).
- Home: the header shows the time once the clock is set; icon pages carry
  only their title. One 32 px icon family (3 px strokes) bobs 2 px over a
  dithered blob shadow that shrinks as it rises; the unread badge rides on
  the Messages bubble; Bluetooth off is the icon at half density.
- Soft corners on every selection, the page pill, tabs and popups;
  dotted scrollbar track with a rounded thumb; the tab bar lays out whole
  tabs and shows edge arrows only in free space.
- DM bubbles drop the sender row and wrap to a second line, with the
  delivery mark and age closing it.
- Keyboards name what is typed (channel, contact, Password, Scope...)
  and show characters left near the limit; PIN entry has its own preview.
- Loading dots for waits (login, scan, GPS) and signal bars in place of
  raw RSSI in Nearby.

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

examples/companion_radio/ui-new/ClockToolsScreen.h

@@ -131,7 +131,7 @@ class ClockToolsScreen : public UIScreen {
       int cx = valx + k * cw;
       if (k == char_idx) {
         d.setColor(DisplayDriver::DARK);
-        d.fillRect(cx, y - 1, cw, d.getLineHeight() + 1);
+        d.fillSoftRect(cx, y - 1, cw, d.getLineHeight() + 1);
         d.setColor(DisplayDriver::LIGHT);
       } else {
         d.setColor(DisplayDriver::DARK);