ci: bake cached toolchain into Podman agent and fix nested Buildah [CI]

ci/publish-dev-node-index.sh

@@ -25,10 +25,12 @@ source "$root/ci/version.sh"
 registry="${ZOT_REGISTRY:-registry.oeo.one}"
 repository="$registry/moshiro-dev/moshiro-$component"
 work="$root/.release/dev-image-index/$component"
-home="/home/justme/woodpecker/buildah-home/dev-node-index-$component"
-export HOME="$home"
+buildah_home="/home/justme/woodpecker/buildah-home/dev-node-index-$component"
+export HOME="$buildah_home"
 export REGISTRY_AUTH_FILE="$work/auth.json"
-mkdir -p "$work" "$home"
+mkdir -p "$work" "$buildah_home"
+source "$root/ci/buildah-env.sh"
+moshiro_setup_buildah "$buildah_home"
 
 logged_in=false
 for attempt in 1 2 3 4; do