Migrate `about` command to new architecture #418

	name: Changelog

	on:
	pull_request:
	branches: [ main ]

	env:
	CARGO_TERM_COLOR: always

	jobs:
	check-for-updates:
	name: Has been updated in this branch

	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v2
	with:
	fetch-depth: 0
	- name: Check file diff
	run: \|
	set -euo pipefail

	if !(git diff origin/main data/changelog.md \| sed '6!d' \| grep -Eq '^* (Bug\|Enhancement\|New):'); then
	echo '
	Please add a brief description of your change to the top of data/changelog.md.
	See existing changes for formatting; accepted tags are "Bug", "Enhancement"
	(minor change to an existing feature), and "New" (completely new feature).
	Contributors are also encouraged to tag changelog entries with their GitHub
	@username.

	Changelog data will be shown on the landing page, in response to the
	`changelog` command, and broadcast to Discord upon release.

	This reminder can be ignored for changes with no user-facing impact, such as
	dependency updates and refactors. Or not! It'"'"'s up to you, really.' >&2

	exit 1
	fi

	- name: Generate release announcement preview
	run: \|
	set -euo pipefail

	changes="$(git diff origin/main data/changelog.md \| awk '/^+[^+]/{ sub(/^[+ ]+/, ""); sub(/^\* /, "\n- "); printf "%s ", $0 }')"$'\n\n'"$(git diff --shortstat origin/main)"
	echo "There's a new release on initiative.sh! Please allow ~5 minutes for the release to appear on production.$changes"

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