Extend the default image provisioning path so opencode is installed through mise as part of both the Go-native image builder and the shell-based rootfs customization flow. That keeps new images consistent regardless of which build path produced them.
The change reuses the existing mise activation setup instead of adding a second tool bootstrap path, and adds a provisioning-script assertion so the generated guest setup includes the opencode install step.
Verified with bash -n customize.sh and go test ./....
Thales Maciel
4e0132982d