Windows support: add "windows" to plugin platforms

[baoyu0]

Summary

herdr-hunk-diff is currently declared macOS/Linux-only, which blocks all of its actions on Windows.

What I did

• Installed the plugin on Windows with herdr plugin install jhochenbaum/herdr-hunk-diff --yes (herdr 0.8.0-preview.2026-08-04-d78e3d3b5126, Node v24.19.0)
• The install succeeded and the plugin was enabled, but the build steps (npm ci, npm run build) are skipped on Windows by herdr, so I built dist/ manually — that worked fine
• After starting a headless server, every action reports:

{"error":{"code":"platform_unsupported","message":"action 'jhochenbaum.hunkdiff.setup-keys' does not support the current platform (windows)"}}

• herdr plugin action list shows all 14 actions with "platforms":["macos","linux"]

Root cause

herdr-plugin.toml line 8:

platforms = ["macos", "linux"]

All action commands are node dist/bin/action.js <action> (cross-platform), and the event/pane commands use sh -c exec node ..., which is available on Windows via Git Bash.

Request

Please add "windows" to the platforms array (or drop the platform restriction if the plugin is expected to be cross-platform), and re-verify the build-skip behavior so Windows installs don't need a manual npm ci && npm run build.

Environment

• OS: Windows 11 (x64)
• herdr: 0.8.0-preview.2026-08-04-d78e3d3b5126
• Node: v24.19.0
• hunk: 0.18.0 (global) / hunkdiff 0.18.1 (bundled)

Happy to test and report back once Windows is supported.