1. **Display Driver Upgrade**
- Replaced simple backlight control with full **Arduino_GFX library** integration
- Configured ST7789 display controller (172x320, with 34px column offset)
- Added SPI bus setup for display communication
2. **Visual Feedback Enhancement**
- Transitioned from binary backlight (ON/OFF) to **full-color screen displays**:
- **Silent state**: Black screen
- **Alarm state**: Red/White blinking
- **Button press**: White screen
- **Silence confirmed**: Green screen with text
- Added colored status messages (WiFi errors, silence confirmations)
3. **Display Test Function**
- New `testDisplay()` cycles through RED → GREEN → BLUE → WHITE → BLACK on startup
- Verifies display hardware functionality
- **Better user feedback**: Color-coded states and text messages replace simple backlight blinking
- **Easier troubleshooting**: Startup test validates display, WiFi errors shown visually with text
- **Enhanced alarm**: Alternating red/white screens more noticeable than simple blinking
- **Hardware utilization**: Fully leverages the 1.47" color LCD instead of treating it as a simple backlight
1. **Hardware switch**: Replaced backlight PWM control (GPIO 22) with WS2812B RGB LED (GPIO 8)
- Removed analog brightness levels (0-255)
- Added bit-bang WS2812B protocol implementation (`setRGB()`)
- Defined color palette: RED, GREEN, BLUE, WHITE, OFF
2. **Visual feedback improvements**:
- **Silent state**: LED OFF (was dim backlight)
- **Alarm state**: Blinks RED/WHITE (was full brightness on/off)
- **Button press**: Shows WHITE while held (was full brightness)
- **Confirmations**: Green flash for SILENCE commands (was dim flash)
3. **Bug fixes**:
- Added edge detection for button to prevent repeated triggers
- Added explicit LED OFF commands throughout setup to prevent lingering states
- Button release now properly resets ALARM → SILENT
4. **Code cleanup**: Removed section divider comments, condensed enum/constant declarations
5. **Tooling**: Added `mise.toml` task for monitor-only (`mon`)
- **More visible alerts**: RGB colors provide clearer state indication than brightness levels
- **Better reliability**: Explicit state management prevents LED staying on unintentionally
- **Improved UX**: Button can now manually cancel alarms with visual confirmation
