Improve detection of selected editor on Windows (#3242)
Improve detection of selected editor on Windows (#3242)

Improves upon previous work completed in #2631:

- Add additional system default check: `JSFile`
- Relax restriction on `.exe` file extension as it is an invalid assumption:

Closes #3223


zeit/hyper,zeit/hyper,zeit/hyper,zeit/hyper,zeit/hyperterm,zeit/hyperterm