fix: vendor ventoy.cpio so builds work after clean clone

The previous commit sourced `ventoy/ventoy.cpio` from
`reference/Ventoy/INSTALL/ventoy/`, but `reference/` is in
.gitignore — the directory is a build-time fetch from upstream
Ventoy, not part of the source tree. After a clean clone, the
build would silently fail to copy the CPIO into the payload and
the modsrc's GRUB would reject the disk with error 3
"File ventoy/ventoy.cpio open failed in VTOYEFI partition".

Move the file to `vendor/ventoy-runtime/ventoy.cpio` (tracked) and
update package_release.sh to read from there. Source is upstream
Ventoy 1.0.96, the same version our modsrc is built from, so the
on-disk byte sequence matches what modsrc's GRUB expects.

scripts/package_release.sh

@@ -129,14 +129,14 @@ fi
 
 # Copy Ventoy's runtime modules into the payload. The modsrc's GRUB
 # binary runs ventoy_check_official_device() at boot, which requires
-# `ventoy/ventoy.cpio` on the ESP. We source this from the upstream
+# `ventoy/ventoy.cpio` on the ESP. We vendor it under
-# Ventoy reference tree (already in the repo for the installer's
+# `vendor/ventoy-runtime/` (sourced from upstream Ventoy 1.0.96, the
-# MBR check); it is a static CPIO blob that doesn't change between
+# same version our modsrc is built from). Without this, the modsrc's
-# Ventoy versions. Without this, the modsrc's GRUB halts with
+# GRUB halts with "This is NOT a standard Ventoy device" before the
-# "This is NOT a standard Ventoy device" before the menu ever renders.
+# menu ever renders.
 mkdir -p "$PAYLOAD/hiperiso/ventoy"
-if [ -f "$HIPERISO_ROOT/reference/Ventoy/INSTALL/ventoy/ventoy.cpio" ]; then
+if [ -f "$HIPERISO_ROOT/vendor/ventoy-runtime/ventoy.cpio" ]; then
-    cp "$HIPERISO_ROOT/reference/Ventoy/INSTALL/ventoy/ventoy.cpio" \
+    cp "$HIPERISO_ROOT/vendor/ventoy-runtime/ventoy.cpio" \
        "$PAYLOAD/hiperiso/ventoy/ventoy.cpio"
 fi