[tmm]

The Rust Release "Plan release" job on 7ae9678 (#197) failed with curl exit 35, a TLS connect error, in one of its crates.io lookups (https://github.com/wevm/zero/actions/runs/43535530530/job/132263485381). The job had set its npm, mirror, and release outputs but not crates. The lookups ran curl -s, so one failed connection failed the job and printed nothing.

The registry and GitHub API lookups in rust-release.yml and swift-release.yml, and the crates.io baseline lookup in rust.yml, now run curl -sS --retry 3 --retry-all-errors:

• Network errors and 408, 429, and 5xx responses are retried 3 times with backoff. A 404 isn't retried. Only a 404 means unpublished, so the decision whether to publish is unchanged.
• If every attempt fails, the step still fails as before, and -S prints curl's error.
• Checked locally with curl 8.14: a TLS failure retries and exits 35, a 503 retries and returns 503, a 404 returns 404 at once, and -w prints the status code once in every case. Both plan scripts, run against the live registries, set every output to false, as main expects with nothing to release.

CI only; no changeset.