mod: improve home screen with adaptive layouts, clock, and set time

- 1-book view: horizontal layout with cover left, title/author right
- 2-3 book view: fix cover stretching by preserving aspect ratio
- 0-book view: show "Choose something to read" placeholder
- Selection highlight now fully contains title and author text
- Add optional clock display in home screen header (AM/PM or 24H)
- Add "Home Screen Clock" setting under Display
- Add "Set Time" activity for manual clock setting via Settings
- Increase homeCoverTileHeight to 310 for title/author breathing room

Co-authored-by: Cursor <cursoragent@cursor.com>

src/CrossPointSettings.h

@@ -128,6 +128,9 @@ class CrossPointSettings {
   // UI Theme
   enum UI_THEME { CLASSIC = 0, LYRA = 1 };
 
+  // Home screen clock format
+  enum CLOCK_FORMAT { CLOCK_OFF = 0, CLOCK_AMPM = 1, CLOCK_24H = 2, CLOCK_FORMAT_COUNT };
+
   // Sleep screen settings
   uint8_t sleepScreen = DARK;
   // Sleep screen cover mode settings
@@ -189,6 +192,9 @@ class CrossPointSettings {
   uint8_t preferredPortrait = PORTRAIT;
   uint8_t preferredLandscape = LANDSCAPE_CW;
 
+  // Home screen clock display format (OFF by default)
+  uint8_t homeScreenClock = CLOCK_OFF;
+
   ~CrossPointSettings() = default;
 
   // Get singleton instance