ZapBox - v938321 - Ambient Lighting Switch

✨ New Feature: Channel 4 Ambient Lighting Switch

• Add special function for channel 4: Ambient lighting mode
• GPIO 11 syncs automatically with display backlight
• Perfect for vending machine lighting that follows screen state
• Display ON → Channel 4 ON (lighting active)
• Screensaver mode → Channel 4 OFF (power saving)
• Only 3 products available in quattro mode when enabled

🔧 Improvements

• Reduced BTC ticker timeout from 15s to 10s
• Increased report screen display time from 2s to 5s
• Reorganized web installer Multi-Channel Mode section
• Changed "Multi-Channel-Control" to "Multi-Channel-Mode"