[Fix] Check if game install folder exists before anything else

[arielj]

Currently, we only check if the game is not available and ask the user if they want to remove it after it failed trying to actually run the game and only if we detect specific error messages.

This created many problems:

• it was doing things like creating a wine prefix first to then fail, so if a user removed the game in that prompt there was a useless prefix left
• it only worked if the error had the appears to be deleted substring, making it kinda brittle
• I understand it was not properly working for amazon games (I've seen many reports about not being able to remove games, but I don't have an account there to test it) because it didn't have that substring

Now, when we want to launch a game, the very first thing we check is if its install folder exists, if it does not we prompt the user if they want to remove the game or not and we don't do anything else.

Closes #3097

---

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)