Feature: Duplicate games with different id to allow using different ocarina codes with the same ISO

[sticks-stuff]

Video demonstration: https://youtu.be/-e-5d-Wpmj4

Made this a while ago assuming USB Loader GX was abandoned, did not know it was still receiving updates.

Mostly opening this PR to gage interest in such a feature, right now the duplicate button only appears in list mode but can easily be added to the other views as well.

[eku]

I'm not quite sure what the use case is? Surely the cheats can be enabled and disabled. So why would you need to duplicate the game?

[sticks-stuff]

It allows using different cheat files on the same SD with the same ISO. If you watch the video you can see how multiple different Brawl mods are able to be loaded which would previously require either swapping out the SD card entirely, or having multiple copies of the ISO with different game IDs on the drive

[eku]

I suggest to use libc i/o function, as done in all other places. C++ streams have a huge memory impact.

[wiidev]

Sorry for the delayed reply! I've been rather busy lately and completely forgot to reply to this 😅

This PR looks okay on the surface, but there are a few issues:

1. It allows users to customise the entire game ID, which isn't safe, as it can result in the loader misidentifying the game type or region, and even assigning the wrong title if the user enters an ID that already exists in wiitdb.xml.
2. It offers no way to remove duplicate games.
3. If the user uninstalls the real game, FullGameList would still contain references (duplicates) to a game that no longer exists, which could break caching.

However, the biggest "issue" is that about six months ago I implemented a setting that allows users to simply enable or disable Project+ if it's detected on their drive. That means the user doesn't need to rename or move files, or configure multiple settings or paths.

If there's enough interest in allowing users to select between multiple Brawl mods, I could probably expand my current on/off selector into a mod selector. But it'd specifically target Brawl, and I'd prefer to only support mods that follow the same naming conventions, since I don't want to add custom code for every mod.

[sticks-stuff]

Would having a different mod selector allow for having the mods listed as different games with their own banner etc? If so, that would definitely supersede this PR

[wiidev]

Currently, no. Before booting the game, if you wanted to change which mod was applied, you'd go into the games settings and select the mod.

I know that's less fancy looking, but it's also much more reliable because users can't input bad game IDs, the games list and cache shouldn't desync if Brawl is deleted or uninstalled, and it doesn't require users to install additional files (such as banners) or relocate or rename a mods files.