Initial commit: Arduino Uno Q USB Audio Synth project

- USB gadget (UAC1 + MIDI) with boot persistence
- USB host mode with auto-detection
- Pure Data synth patch with ALSA + UDP netreceive MIDI input
- MIDI rawmidi-to-UDP bridge (midi-bridge.py)
- LED matrix visualization (led-matrix-viz.py via arduino-router RPC)
- MCU sketch for LED matrix control (Arduino_RouterBridge + ArduinoGraphics)
- Conftest/OPA Rego policy validation suite for .pd files
- gen_synth_pd.py: programmatic .pd file generator
- System services: midi-bridge, led-matrix-viz, pd-synth-auto, usb-role-detect
- Justfile with deploy, enable, diagnostic recipes
- Diagnostic script (diag.sh)

install.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+# install.sh — Install system dependencies on the Uno Q
+# Run this on the board: ssh arduino@uno-q.local 'bash -s' < install.sh
+
+set -euo pipefail
+
+echo "[INSTALL] Updating packages..."
+sudo apt update -qq
+
+echo "[INSTALL] Installing Pure Data..."
+sudo apt install -y -qq puredata alsa-utils
+
+echo "[INSTALL] Installing USB gadget config..."
+sudo cp system/configure-usb-audio.sh /usr/local/bin/
+sudo chmod +x /usr/local/bin/configure-usb-audio.sh
+sudo cp system/asound.conf /etc/asound.conf
+
+echo "[INSTALL] Installing systemd services..."
+sudo cp system/usb-gadget-audio.service /etc/systemd/system/
+sudo cp system/pd-synth.service /etc/systemd/system/
+sudo systemctl daemon-reload
+
+echo "[INSTALL] Enabling services..."
+sudo systemctl enable usb-gadget-audio
+sudo systemctl enable pd-synth
+
+echo "[INSTALL] Done. Reboot with: sudo reboot"