synth-diagnostic starts pipeline services, cleans up on failure

- run-tests.sh: starts pipeline services, runs test-unit.py,
  stops services on failure, leaves running on success
- synth-diagnostic is the single gate for pipeline startup
- deploy: stop pipeline → restart prometheus → start synth-diagnostic
  (synth-diagnostic starts pipeline on success)

justfile

@@ -104,9 +104,9 @@ deploy:
         cd {{REPO_DIR}} && git pull && \
         chmod +x scripts/*.py scripts/*.sh 2>/dev/null; \
         echo '{{BOARD_PASS}}' | sudo -S systemctl daemon-reload && \
+        echo '{{BOARD_PASS}}' | sudo -S systemctl stop midi-bridge pd-synth-onboard led-matrix-viz && \
         echo '{{BOARD_PASS}}' | sudo -S systemctl restart prometheus-exporter && \
         echo '{{BOARD_PASS}}' | sudo -S systemctl start synth-diagnostic && \
-        echo '{{BOARD_PASS}}' | sudo -S systemctl restart midi-bridge pd-synth-onboard led-matrix-viz && \
         echo '[OK] Deployed + restarted'"
 
 # Start synth (onboard audio)

scripts/run-tests.sh

@@ -1,19 +1,25 @@
 #!/bin/bash
-# run-tests.sh — wrapper for test-unit.py with exit code mapping
+# run-tests.sh — start services, run tests, clean up on failure
 set -euo pipefail
 
 BOARD="${BOARD_HOST:-192.168.9.167}"
 cd /home/arduino/uno-q-audio-synth
 
-echo "[diag] Running synth pipeline diagnostics against $BOARD..."
+echo "[diag] Starting pipeline services for diagnostics..."
+sudo systemctl start midi-bridge pd-synth-onboard led-matrix-viz
 
+echo "[diag] Waiting 3s for services to settle..."
+sleep 3
+
+echo "[diag] Running synth pipeline diagnostics against $BOARD..."
 python3 scripts/test-unit.py "$BOARD"
 exit_code=$?
 
 if [ $exit_code -eq 0 ]; then
-    echo "[diag] All tests PASSED — pipeline healthy"
+    echo "[diag] All tests PASSED — pipeline healthy, leaving services running"
 else
-    echo "[diag] Tests FAILED (exit $exit_code) — check dashboard for details"
+    echo "[diag] Tests FAILED (exit $exit_code) — stopping pipeline services"
+    sudo systemctl stop midi-bridge pd-synth-onboard led-matrix-viz
 fi
 
 exit $exit_code