feat(windows)!: Drop Windows support

[breautek]

Platforms affected

Windows

Motivation and Context

Windows platform has been deprecated in favour for Electron. This plugin still has browser support, which electron will use as a fallback. As far as I can see in GitHub Actions, there are no tests for windows platform. This plugin is far behind as it is, so may as well reduce our burden.

Description

Removes the windows proxy sources and drop the meta information in plugin.xml / package.json

Testing

Ran npm test, but that only runs eslint.

Checklist

• [x] I've run the tests to see all new and existing tests pass
• [x] I added automated test coverage as appropriate for this change
• [x] Commit is prefixed with (platform) if this change only applies to one platform (e.g. (android))
• [x] If this Pull Request resolves an issue, I linked to the issue in the text above (and used the correct keyword to close issues using keywords)
• [x] I've updated the documentation if necessary