fix: e-ink portrait/landscape layout — separators, battery, keyboard, screens

- DisplayDriver: add sepH() (2px landscape, 1px OLED); fix transliterateCodepoint
  fallback '?' (was '\xDB' which broke UTF-8 word-wrap and rendered tiny block char)
- GxEPDDisplay: drawRect draws double border on landscape for visible 2px weight
- UITask: navigation dots scale with lh; content_y saves 16px by using dots_y+6;
  battery iconW=lh*2, fill margin bm scales with orientation; indicator spacing fixed;
  clock separator uses sepH(); alert popup tight and vertically centred
- KeyboardWidget: compact cell height (no stretch), multi-line preview, cursor always
  on last visible line
- BotScreen / NearbyScreen detail: use lineStep() as natural item height, shrink only
  when items don't fit (fixes portrait stretch)
- QuickMsgScreen: send button pinned to display bottom (height-lh-2), not floating
- SettingsScreen: AUTO_OFF guarded with #if AUTO_OFF_MILLIS>0; default sel=AUTO_LOCK
- All screens: separators updated to sepH()

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

examples/companion_radio/ui-new/DashboardConfigScreen.h

@@ -46,7 +46,7 @@ public:
     int val_x   = display.valCol();
 
     display.drawTextCentered(display.width() / 2, 0, "CLOCK FIELDS");
-    display.fillRect(0, display.headerH() - 1, display.width(), 1);
+    display.fillRect(0, display.headerH() - 1, display.width(), display.sepH());
 
     static const char* labels[] = { "Field 1", "Field 2", "Field 3" };
     for (int i = 0; i < FIELD_SLOTS; i++) {