Introduce Enable Gamescope toggle

[Etaash-mathamsetty]

Should fix some of the confusion that was caused by the additional options text field

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)

[arielj]

with this change we'll be disabling gamescope for all users that currently have it configured with the other checkboxes until they go and manually enable it

Maybe we need some code setting the initial enableGamescope setting to be the value of gameSettings.gamescope?.enableLimiter || gameSettings.gamescope?.enableUpscaling. Or maybe we can type it as boolean | null and default it to null with null meaning it was never set, use the previous logic?