Fix the S3 publish summary, and add a changelog and ADR

[t4k]

Three things, all arising from the first dry run against the released @v1.

1. The summary step failed after a successful publish

✓ Build the bundles
✗ Run caltechlibrary/workflows/.github/actions/publish-to-s3@v1
    ==> dist -> s3://***/cl-webcomponents/
    ==> css  -> s3://***/cl-webcomponents/css/
    ==> would invalidate /cl-webcomponents/* on ***
    publish-to-s3: dry run done
    ##[error]Process completed with exit code 1

[ "$COUNT" -gt 40 ] && echo "- …and $((COUNT - 40)) more"

Returns 1 when the count is below the threshold, and it was the last command in the block. Composite action steps run with bash -eo pipefail, so the step failed. Replaced with an if.

It triggers on uploads of 40 files or fewer — every realistic upload — so v1 is currently broken for any consumer.

CI missed it because publish-to-s3-guards exercises bin/publish-to-s3.sh, while this lived in the action's summary step, reachable only by running the action end to end. That needs AWS credentials this repository deliberately does not hold, so a consuming repository's dry run is the test — working as intended, just later than ideal.

2. CHANGELOG.md

Following Keep a Changelog 1.1.0, with v1.0.0 and v1.1.0 reconstructed.

Consumers reference @v1, which moves. Until now there was no way to learn what moved short of reading commits — the one real cost of a moving major tag. CONTRIBUTING.md now asks for an entry with any change that reaches a consumer.

3. ADR-0007 — constraints on publishing to the media bucket

Four choices in publish-to-s3 that each look like an oversight and each cause a visible outage if "corrected":

Choice	What breaks if changed
cp, never sync --delete	removes the fonts/ directory, which exists in no repository — every site using footer-global loses its typeface
keep --acl public-read	the bucket has no policy; uploads succeed but are invisible to anonymous readers
explicit content types	the CLI's guess omits the charset and has changed between versions, so what the CDN serves changes for files nobody edited
invalidate /$PREFIX/*, not /*	discards every other project's cached objects and bills per path

All four were defended only by comments in the script. A comment does not survive someone rewriting the file it lives in, and the failure modes are not guessable from the code.

The ADR also records the order for the bucket migration that would relax two of them — policy first, verify, then BucketOwnerEnforced — since doing it in any other order takes the distribution down.

After merging

v1 needs to move again, since the released one still has the bug. Then I'll re-run the consumer dry run before opening the CL-web-components caller.

🤖 Generated with Claude Code