1.0.0

ci: add Windows installer build + GitHub release publishing

electron-builder already produces an NSIS installer and a portable exe
(npm run dist) but nothing ever built or published one — no workflow, no
releases. Adds a windows-latest Actions job that builds and publishes both
via electron-builder's github provider on a v* tag push or manual dispatch,
and pins the artifact filenames (PathForge-Setup.exe / PathForge-Portable.exe)
so releases/latest/download/<name> is a stable link across versions instead
of breaking on every version bump.