[GOG]: Support overlay

[imLinguin]

This PR will cover Linux and maybe Windows
PR plan:

• [ ] Add option to download/update comet's overlay and web components
• [ ] Update gogdl itself to inject the overlay on Windows
• [x] Ship galaxy-helper and add support for it in gogdl (requires https://github.com/Heroic-Games-Launcher/heroic-gogdl/commit/9079373d6fd7904f6c639d531b9c1877ea4a03c1)

As I don't own a Mac and can't confidently write support for usage of native overlay build over there

Use the following Checklist if you have changed something on the Backend or Frontend:

• [ ] Tested the feature and it's working on a current and clean install.
• [ ] Tested the main App features and they are still working on a current and clean install. (Login, Install, Play, Uninstall, Move games, etc.)
• [ ] Created / Updated Tests (If necessary)
• [ ] Created / Updated documentation (If necessary)