Add CONTROL_SERVER_HOST to allow external connections

- Add CONTROL_SERVER_HOST environment variable (default: 0.0.0.0)
- Server now binds to all interfaces by default for external access
- Update .env and .env.example with new host configuration
- Allows UI clients to connect from other machines on the network

.env.example

@@ -15,6 +15,11 @@ CONTROL_SERVER_URI=ws://10.42.0.1:8765
 # For custom IP (if your Pi has a different address):
 # CONTROL_SERVER_URI=ws://YOUR_PI_IP:8765
 
+# Control server WebSocket host (bind address)
+# 0.0.0.0 = listen on all interfaces (allows external connections)
+# localhost or 127.0.0.1 = listen only on localhost (local only)
+CONTROL_SERVER_HOST=0.0.0.0
+
 # Control server WebSocket port
 CONTROL_SERVER_PORT=8765
 
@@ -29,7 +34,7 @@ TRANSPORT=spi
 # Sound Detection Configuration
 # ==============================
 # Audio input device index (use sound.py to list available devices)
-AUDIO_INPUT_DEVICE=7
+AUDIO_INPUT_DEVICE=1
 
 # MIDI TCP configuration
 MIDI_TCP_HOST=127.0.0.1