Initial commit: OCI image mounting via containers-storage

slocker-lite validates an OCI Image Layout tar, imports its layers into
containers-storage's layer store in order, and mounts the assembled image
using fuse-overlayfs, printing the resulting merged path.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

add-license.sh

@@ -0,0 +1,10 @@
+#! /bin/bash
+
+if [[ $1 = -f ]]; then
+	shift
+	for i in "$@"; do
+		grep -q 'GNU General Public License' "$i" || sed -i '0 r copyright-header' "$i"
+	done
+else
+	find src/ \( -name \*.c -o -name \*.cpp -o -name \*.h \) -exec "$0" -f {} +
+fi