Add auto-sleep timeout setting and handle it in loop

Incremented settings count, added autoSleepMinutes to CrossPointSettings, updated save/load functions, and integrated auto-sleep logic based on the new setting.

src/activities/settings/SettingsActivity.cpp

@@ -9,7 +9,7 @@
 
 // Define the static settings list
 namespace {
-constexpr int settingsCount = 13;
+constexpr int settingsCount = 14;
 const SettingInfo settingsList[settingsCount] = {
     // Should match with SLEEP_SCREEN_MODE
     {"Sleep Screen", SettingType::ENUM, &CrossPointSettings::sleepScreen, {"Dark", "Light", "Custom", "Cover"}},
@@ -35,6 +35,10 @@ const SettingInfo settingsList[settingsCount] = {
     {"Reader Font Size", SettingType::ENUM, &CrossPointSettings::fontSize, {"Small", "Medium", "Large", "X Large"}},
     {"Reader Line Spacing", SettingType::ENUM, &CrossPointSettings::lineSpacing, {"Tight", "Normal", "Wide"}},
     {"Cover Art Picker", SettingType::TOGGLE, &CrossPointSettings::useCoverArtPicker, {}},
+    {"Auto Sleep Timeout",
+     SettingType::ENUM,
+     &CrossPointSettings::autoSleepMinutes,
+     {"5 min", "10 min", "15 min", "20 min", "30 min", "60 min", "Never"}},
     {"Bluetooth", SettingType::TOGGLE, &CrossPointSettings::bluetoothEnabled, {}},
     {"Check for updates", SettingType::ACTION, nullptr, {}},
 };