Use XmlSerializer over BinaryFormatter

[Emik03]

BinaryFormatter will become fully deprecated in .NET 9, and already throws exceptions in .NET 8 since it's opt-in now. This pull request makes migrations to .NET 8 and up possible.

XmlSerializer in this case is an easy swap-in replacement. There may be some performance implications, but I haven't noticed any regressions when previewing or playing charts in the Quaver game, including extremely heavy/dense charts.

[Warp9000]

I feel like theres better ways of cloning objects than serializing and deserializing

[Emik03]

I feel like theres better ways of cloning objects than serializing and deserializing

Agreed! I would personally make every class derive from ICloneable and give deep clone implementations, however this is a refactor job that I would want explicit approval of since it's a larger time commitment than swapping 2 lines of code.

[Cuckson]

I think XElement would be a bit more efficient than serialization if you're worried about the performance.

[Illuminati-CRAZ]

The documentation for ICloneable recommends against implementing it for public APIs

[Emik03]

The documentation for ICloneable recommends against implementing it for public APIs

We can always make a ICopyable<T> or similar interface, or just straight up include .Clone()/.Copy() functions without any polymorphism capabilities. The point here more is that these classes should have dedicated functions to perform deep copies.