Update externality to v0.1.1

Editor assessment

The subject states the exact dependency move — externality to v0.1.1 — and the resolves #1275 footer is well formed, tying the bump to the issue it fixes and giving the update a reason, which elevates it above a bare version change. The fix classification fits an issue-driven update. Hygiene is clean: imperative mood, no trailing period, sensible length. No body is needed because the footer carries the motivation pointer. Accurate, complete, and purposeful for its size: a good, publishable example.