Consolidate `UnusableDependencies` into a generic `Unavailable` incom… #19

	# Automatically creates a tag for each commit to `main` so when we rebase
	# changes on top of the upstream, we retain permanent references to each
	# previous commit so they are not orphaned and eventually deleted.
	name: Create permanent reference

	on:
	push:
	branches:
	- "main"

	jobs:
	create-permaref:
	runs-on: ubuntu-latest
	steps:
	- name: Checkout
	uses: actions/checkout@v4

	- name: Get the permanent ref number
	id: get_version
	run: \|
	# Enable pipefail so git command failures do not result in null versions downstream
	set -x

	echo "LAST_PERMA_NUMBER=$(\
	git ls-remote --tags --refs --sort="v:refname" \
	https://github.com/zanieb/pubgrub.git \| grep "tags/perma-" \| tail -n1 \| sed 's/.*\/perma-//' \
	)" >> $GITHUB_OUTPUT

	- name: Configure Git
	run: \|
	git config user.name "$GITHUB_ACTOR"
	git config user.email "[email protected]"

	- name: Create and push the new tag
	run: \|
	TAG="perma-$((LAST_PERMA_NUMBER + 1))"
	git tag -a "$TAG" -m 'Automatically created on push to `main`'
	git push origin "$TAG"
	env:
	LAST_PERMA_NUMBER: ${{ steps.get_version.outputs.LAST_PERMA_NUMBER }}

Provide feedback