Adds `cargo fmt --check` (stock defaults) to ci.yaml's gate, now that the
tree is rustfmt-clean (commit 41b7e9a). Records that reformat in
.git-blame-ignore-revs so `git blame` skips it. Amends ADR-ci-002 (the
deferred "revisit on main" fmt decision) + the ci ADR index.
Closes#35.
Add website/** and the website workflow to ci.yaml's paths-ignore, so a
push confined to the website subproject (built + published by
website.yaml) no longer runs clippy+test. A push that also touches crate
code still gates (paths-ignore skips only when all files match).
Add paths-ignore (docs/**, **/*.md) to the gate's push + pull_request
triggers so markdown/docs-only changes don't run a full clippy+test that
can't change the outcome. Mixed code+docs pushes still gate (not all
files are ignored); flake/toolchain changes are deliberately not ignored.
Also refresh a stale ADR-0049 -> ADR-ci-002 comment reference.
Tag pushes ignore paths: filters, so a release tag spuriously rebuilt
the unchanged CI image and re-ran the gate on a commit the branch push
already gated. Add branches: ['**'] to both push triggers — tag pushes
no longer fire them (release.yaml owns tags). Pushing commits + a tag
together still gates the commits via the branch push.