[epic] Windows distribution — .exe / portable build

[ikseong00]

Goal

Produce a downloadable Windows installer (.exe via NSIS) and/or portable build of Tokie, attached to a GitHub Release.

Why

Windows users are currently locked out — no installer, can only run from source. To make Tokie a real cross-platform thing this needs to ship.

Acceptance

• package.json build.win section configured (NSIS target).
• npm run dist (or a Windows-specific script) produces Tokie-Setup-<v>.exe on a Windows build machine or GitHub Actions windows runner.
• Installer runs end-to-end on Win 10/11: install → launch → pet hatches.
• userData path on Windows is %APPDATA%\token-eater-pet\ (kept for compat with macOS naming — see electron/main.ts app.setPath).
• Tray icon visible on Windows taskbar (current SVG icon may need a .ico conversion).
• Artifact attached to a GitHub Release.

Hints

• Easiest path: GitHub Actions windows-latest runner, electron-builder cross-build. No Windows hardware required.
• statusLine shim (scripts/statusline-shim.cjs) — confirm it works on Windows. Path separators + the http POST should be portable.
• chokidar watcher on JSONL — works on Windows but path handling for ~/.claude differs. Test that.
• Tray icon: macOS uses 18x18 PNG, Windows wants .ico for best result. Generate a multi-resolution .ico from the existing icon.

Out of scope

• Code signing on Windows (EV cert ≠ trivial; separate issue if pursued).
• Linux builds (separate).