fix: include build-debug.sh and motd changes missed from previous commit

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

iso/builder/build-debug.sh

@@ -118,6 +118,12 @@ cp "${NVIDIA_CACHE}/bin/nvidia-smi" "${OVERLAY_DIR}/usr/local/bin/"
 chmod +x "${OVERLAY_DIR}/usr/local/bin/nvidia-smi"
 cp "${NVIDIA_CACHE}/lib/"* "${OVERLAY_DIR}/usr/lib/" 2>/dev/null || true
 
+# --- inject build info into motd ---
+BUILD_DATE=$(date +%Y-%m-%d)
+GIT_COMMIT=$(git -C "${REPO_ROOT}" rev-parse --short HEAD 2>/dev/null || echo "unknown")
+BUILD_INFO="${BUILD_DATE} git:${GIT_COMMIT} alpine:${ALPINE_VERSION} nvidia:${NVIDIA_DRIVER_VERSION}"
+sed -i "s/%%BUILD_INFO%%/${BUILD_INFO}/" "${OVERLAY_DIR}/etc/motd"
+
 # --- build ISO using mkimage ---
 mkdir -p "${DIST_DIR}"
 echo ""