Add x86_64 kernel bring-up with build-selected platform adapters

toolchain/compile_isogen.sh

@@ -1,8 +1,15 @@
 #!/usr/bin/env bash
+# Multi-architecture build updates: Copyright 2026 Aaron Hance.
+set -e
+source "$(dirname "${BASH_SOURCE[0]}")/target.sh"
 echo " "
 echo "======================="
 echo " "
 echo "Creating ISO..."
 echo " "
-cp bin/kernel.bin iso/boot/asuro.bin
-grub-mkrescue -o Asuro.iso iso
+mkdir -p "$ISO_ROOT/boot/grub"
+if [ "$ASURO_ARCH" != x86 ]; then
+    cp iso/boot/grub/grub.cfg "$ISO_ROOT/boot/grub/grub.cfg"
+fi
+cp "$BIN_DIR/kernel.bin" "$ISO_ROOT/boot/asuro.bin"
+grub-mkrescue -o "$ISO_FILE" "$ISO_ROOT"