Read PNPM version from package.json

Allow PNPM toolchain to read version from a package.json file i.e.

{
  "devEngines": {
    "packageManager": {
      "name": "pnpm",
      "version": "11.25.0",
      "onFail": "download"
    }
  }
}

• Path must be supplied and could be relative to project directory
• Fail if not of type pnpm and if version is not semantic version.