Fixes
- Settings persistence: clock/weather settings no longer reset to ON after reboot
- Remove keepClockAlive: prevents accidental battery drain (~3-4mA in deep sleep)
- Text darkness restored: works in both BW mode (threshold) and grayscale mode (preserves anti-aliasing)
- OTA update: fix chunked HTTP response handling from GitHub API
- Manual refresh mode: added "Off" option to refresh frequency — manually refresh with power button
- Lexend font: reverted weight from 350 back to 400
- Text Darkness setting: moved to CrossPet settings tab