Dual improvements

[orwenn22]

this pr contains some improvements for dual maps

this is far from being finished, but i'm opening this just in case anything in here end up actually being useful for anything in the future in case i don't actually finish this

• dual maps are now imported properly
• in order to store dual scores properly, i created a "PlayerScore" class, and moved all the scoring related stuff in there, and the ScoreInfo class new contains an array of PlayerScore
• the result screen can display the result of both players. it is possible to switch between players by clicking on the pfps at the top right, and clicking on the player that is already selected opens his profile in order to keep the old behaviour
• all players' scores should have a maximum value of 1000000 with no mods applied, and the easy/hard mods work properly

2025-11-21.13-53-54.mp4

there are a few things that i want to do but are not there yet, such as

• fix the MaxCombo value being incorrect in the result screen
• add some sort of filters in the song select's leaderboard to allow getting the score for each sides separately, and also sorting by total score
• make it possible to create dual maps without having to edit the file manually
• ability to play dual maps in multiplayer
• actually write the realm migration (and fix the one i broke due to the changes)

fluxel branch (barely contains anything for now) : https://github.com/orwenn22/fluxel/tree/dual-iimprovements

[flustix]

RealmPlayerScore should probably inherit EmbeddedObject since it can't be used for multiple scores at the same time.