The Release pnpm (Rust) workflow renamed the built binary to `pnpm` at the
repo root before tarring it. Since the pacquet/ directory was renamed to
pnpm/, that `mv` moved the binary *into* the existing `pnpm/` source
directory instead, so the non-Windows archives contained the whole Rust
source tree. The publish job then extracted a directory where it expected a
binary and failed with EISDIR in generate-packages.mjs
(https://github.com/pnpm/pnpm/actions/runs/29113833296).
Stage the binary in a scratch directory and tar from there, keeping the
archive layout (a plain `pnpm` binary at the root) unchanged.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
