* feat: support pnpm v12
Approve the pinned @pnpm/exe install script for npm 12, add pnpm 12 coverage across supported runner platforms, and clarify that action-setup remains supported alongside pnpm/setup.
* refactor: use pnpm 12 native bootstrap
Install the plain pnpm v12 package as the single native bootstrap, remove the legacy @pnpm/exe lockfile and runtime path, and retain the standalone input as a no-op for workflow compatibility.
* fix: keep bootstrap updates on pnpm 12
Handle npm's array-shaped view output and resolve only pnpm 12 distribution tags.
* fix: use native bootstrap only for pnpm 12
Route pnpm 12-only versions and ranges through the plain pnpm native package while preserving the existing Node and @pnpm/exe bootstrap paths for older releases.
* style: remove updater narrative comments
Zoltan Kochan