v0.5.0

• One BlueSCSI firmware image for all boards: the panel auto-detects the host
  transport (v2 = I2C, Ultra/Ultra Wide = SPI) at boot and remembers it, so
  bluescsi-frontpanel.bin replaces the separate -ultra/-v2 images
• Recover the OLED when it misses power-on init (slow 3V3 ramp on host power)
• Show the SD-card panel update path in the BlueSCSI web UI