feat(eink): scale size-1 font with display orientation

Portrait mode (122px wide) matches the OLED's ~21 chars/line with a 1× font.
Landscape mode (250px wide) was using the same small 6×8 font, leaving text
physically tiny and the wide display underutilised.

Size 1 now scales by orientation: 1× (6×8 / Lemon 5×10) in portrait,
2× (12×16 / Lemon 10×20) in landscape. Size 2 stays at 12×16 and size 3
at FreeSans18pt in both orientations — their layout Y-positions are hardcoded
so they cannot be scaled without a full layout refactor.

fontAscender() updated to accept a scale parameter; Lemon ascender becomes
8×scale (8px portrait, 16px landscape) to keep top-of-cell coordinate
semantics consistent with the rest of the UI code.

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

src/helpers/ui/GxEPDDisplay.cpp

@@ -16,9 +16,9 @@
 // GFX fonts use the baseline as the cursor origin. UI code assumes top-of-cell
 // coordinates (same convention as the OLED driver). Add the font ascender so
 // the two conventions match.
-static int fontAscender(int sz, bool use_lemon) {
+static int fontAscender(int sz, bool use_lemon, int scale) {
-  if (sz == 3) return 26;    // FreeSans18pt7b: proportional font, baseline origin
+  if (sz == 3) return 26;              // FreeSans18pt7b: proportional, baseline origin
-  if (use_lemon) return 8;   // Lemon GFX font: baseline origin, typical ascender 8px
+  if (use_lemon) return 8 * scale;    // Lemon GFX font: baseline origin, ascender 8px×scale
   return 0;                           // GFX built-in font: cursor is top-left of cell
 }
 
@@ -72,14 +72,19 @@ void GxEPDDisplay::startFrame(Color bkg) {
   display.fillScreen(GxEPD_WHITE);
   display.setTextColor(_curr_color = GxEPD_BLACK);
   _text_sz = 1;
+  int sc = (width() >= height()) ? 2 : 1;
   display.setFont(_use_lemon ? &Lemon : NULL);
-  display.setTextSize(1);
+  display.setTextSize(sc);
   display_crc.reset();
 }
 
 void GxEPDDisplay::setTextSize(int sz) {
   _text_sz = sz;
   display_crc.update<int>(sz);
+  // Size 1 scales with orientation: 1× in portrait (≈OLED width), 2× in landscape.
+  // Size 2 always uses 2× built-in (12×16) — fixed because layout Y-positions are hardcoded.
+  // Size 3 always uses FreeSans18pt for large headings.
+  int sc = (width() >= height()) ? 2 : 1;
   switch (sz) {
     case 3:
       display.setFont(&FreeSans18pt7b);
@@ -91,7 +96,7 @@ void GxEPDDisplay::setTextSize(int sz) {
       break;
     default:
       display.setFont(_use_lemon ? &Lemon : NULL);
-      display.setTextSize(1);
+      display.setTextSize(sc);
       break;
   }
 }
@@ -111,7 +116,8 @@ void GxEPDDisplay::setCursor(int x, int y) {
   display_crc.update<int>(y);
   // Offset y by the font ascender: callers pass top-of-cell y, GFX fonts
   // expect baseline y. Without this, text would be clipped at the top.
-  display.setCursor(x, y + fontAscender(_text_sz, _use_lemon));
+  int sc = (width() >= height()) ? 2 : 1;
+  display.setCursor(x, y + fontAscender(_text_sz, _use_lemon, sc));
 }
 
 void GxEPDDisplay::print(const char* str) {

src/helpers/ui/GxEPDDisplay.h

@@ -68,11 +68,20 @@ public:
   //   1 = FreeSans9pt      (lineH=16, charW≈9)
   //   2 = FreeSansBold12pt (lineH=20, charW≈12)
   //   3 = FreeSans18pt     (lineH=28, charW≈17)
-  // Size 1: GFX built-in 6×8 (default) or Lemon 5×10 bitmap font — matches OLED metrics.
+  // Size 1 scales with orientation (portrait 1×, landscape 2×); size 2 is always 12×16;
-  // Size 2: GFX built-in scaled 12×16 bitmap font.
+  // size 3 is FreeSans18pt (~17×28). Landscape = width >= height.
-  // Size 3: FreeSans18pt proportional font for large headings.
+  int getCharWidth() const override {
-  int getCharWidth()  const override { return _text_sz == 3 ? 17 : _text_sz == 2 ? 12 : (_use_lemon ? 5 : 6); }
+    int sc = (width() >= height()) ? 2 : 1;
-  int getLineHeight() const override { return _text_sz == 3 ? 28 : _text_sz == 2 ? 16 : (_use_lemon ? 10 : 8); }
+    if (_text_sz == 3) return 17;
+    if (_text_sz == 2) return 12;
+    return (_use_lemon ? 5 : 6) * sc;
+  }
+  int getLineHeight() const override {
+    int sc = (width() >= height()) ? 2 : 1;
+    if (_text_sz == 3) return 28;
+    if (_text_sz == 2) return 16;
+    return (_use_lemon ? 10 : 8) * sc;
+  }
   void setLemonFont(bool enabled) override { _use_lemon = enabled; }
 
   bool begin();