Pins actions/checkout v7.0.1, actions/upload-artifact v7.0.2, actions/download-artifact v8.0.2 and
Swatinem/rust-cache v2.9.2 by commit. Re-applied onto current main by the maintainer (the workflows
changed since the PR was opened); dtolnay/rust-toolchain stays on @stable, because pinned to a commit
it needs an explicit toolchain input, and it is a composite action with no Node runtime.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RjGw4gA5ZvKrU8MQP6sBgT
