feat: add screen timeout & Energy Saver

[emaza]

Feature: Screen Timeout & Energy Saver
📝 Description
Implements an automatic screen timeout feature to turn off the display after 20 seconds of inactivity. This helps in reducing power consumption and keeping the device temperature lower.

✨ Changes

• Added global activity timer (lastActivityTime) and screen state tracker (isScreenOn).
• Implemented
• checkScreenTimeout()
• in the main loop to handle auto turn-off.
• Added wrappers for button callbacks (- onSwitchToNextScreen, - onAlternateScreenRotation, etc.) to:
  - Wake up the screen if it's off.
  - Reset the activity timer on any interaction.
  - Execute the original button action.

🧪 Verification

• Timeout: Verified that the screen turns off after 20 seconds of no interaction.
• Wake Up: Verified that pressing any button wakes up the screen immediately.
• Functionality: Verified that button actions (change screen, rotate) still work correctly after waking up.
• checked in T-Display-S3 ESP32-S3