refactor(relay): add --smoke entrypoint

scripts/package-mac-app.sh

@@ -255,7 +255,7 @@ if [[ "${SKIP_GATEWAY_PACKAGE:-0}" != "1" ]]; then
   rm -rf "$RELAY_BUILD_DIR"
 
   echo "🧪 Smoke testing bundled relay QR modules"
-  CLAWDBOT_SMOKE_QR=1 "$RELAY_OUT" >/dev/null
+  "$RELAY_OUT" --smoke qr >/dev/null
 
   echo "🎨 Copying gateway A2UI host assets"
   rm -rf "$RELAY_DIR/a2ui"