Local iteration with OCI snapshots

Test addon changes without pushing to GitHub:

shoulders up --local     # fresh cluster, Flux reconciles from your working tree
# ... edit 2-addons/... ...
shoulders sync           # push a new snapshot tag and wait for Flux to reconcile
shoulders sync --wait=false  # push and request reconcile without blocking

sync waits up to 10 minutes by default (--timeout overrides). On vind with no ociRepository.url configured, both commands create a throwaway in-cluster registry automatically. Every snapshot gets an immutable local-<sha>-<timestamp>[-dirty] tag.

Raw script path:

SHOULDERS_FLUX_SOURCE=oci SHOULDERS_OCI_URL=... SHOULDERS_OCI_TAG=... 2-addons/install-addons.sh