Guard staged node-pty ASAR path rewrites so already-unpacked paths are
not rewritten twice. Normalize spawn-helper to mode 0755 in both the
prebuild and locally compiled build/Release staging paths.
Add behavioral coverage for both unpacked path forms and both helper
layouts.
Co-authored-by: zhouwei <zwcf5200@163.com>
Co-authored-by: liuhao1024 <sunsky.lau@gmail.com>
