The actions dtolnay/rust-toolchain@stable, swatinem/rust-cache@v2, and dtolnay/rust-toolchain@nightly are not allowed in BuildMonumental/ustr because all actions must be from a repository owned by BuildMonumental, created by GitHub, or match one of the patterns: NixOS/nix-installer-action@*, anthropics/claude-code-action@*, astral-sh/setup-uv@*, aws-actions/configure-aws-credentials@*, dorny/paths-filter@*, opentofu/setup-opentofu@*, oven-sh/setup-bun@*, ravsamhq/notify-slack-action@*, stefanzweifel/git-auto-commit-action@*, tailscale/*.