feat(ui): status-bar mini-icons + settings fixes

- Replace single-letter M/B/A/G top-bar indicators with scalable mini-icons:
  ICON_MUTE (speaker+cross), ICON_BLUETOOTH (rune), ICON_ADVERT (broadcast
  mast+waves), ICON_TRAIL (map pin). Centred in the cw+2 indicator box;
  disconnected BT shows the plain glyph instead of lowercase b.
- fix(settings): right-side values used display.valCol() without the scrollbar
  reserve, so after expanding a section they rendered under the indicator.
  Route all value cursors through valCol(display) = display.valCol() - _reserve.
- fix(settings): font toggle used ^=1, which on a stale value of 2 (older Hybrid
  build) flips 2<->3 — both nonzero, locking applyFont() on Lemon with no way
  back. Normalise: use_lemon_font = use_lemon_font ? 0 : 1.
- docs(settings): document Messages > Resend setting.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

examples/companion_radio/ui-new/icons.h

@@ -118,6 +118,39 @@ MINI_ICON(ICON_CROSS, 4,   // ✗
   packRow(".##."),
   packRow("#..#"));
 
+// Top-bar status glyphs (replace the single-letter M / B / A indicators).
+MINI_ICON(ICON_MUTE, 6,   // speaker + cross (sound off)
+  packRow("..#..."),
+  packRow(".##..."),
+  packRow("####.#"),
+  packRow("###.#."),
+  packRow("####.#"),
+  packRow(".##..."),
+  packRow("..#..."));
+MINI_ICON(ICON_BLUETOOTH, 5,   // ᛒ bluetooth rune
+  packRow("..#.."),
+  packRow("..##."),
+  packRow("#.#.#"),
+  packRow(".###."),
+  packRow("#.#.#"),
+  packRow("..##."),
+  packRow("..#.."));
+MINI_ICON(ICON_ADVERT, 6,   // broadcast mast + radiating waves (auto-advert)
+  packRow("#....#"),
+  packRow(".#..#."),
+  packRow("..##.."),
+  packRow("..##.."),
+  packRow(".####."),
+  packRow(".####."));
+
+MINI_ICON(ICON_TRAIL, 6,   // map pin / location marker (GPS trail logging)
+  packRow(".####."),
+  packRow("######"),
+  packRow("##..##"),
+  packRow("######"),
+  packRow(".####."),
+  packRow("..##.."));
+
 // Keyboard special-key glyphs.
 MINI_ICON(ICON_SHIFT, 7,   // ⇧  caps
   packRow("...#..."),