Document bitmask C# API difference

[LemmaEOF]

I spent a good couple hours today beating my head against an inscrutable C# compile error tonight that ended up being because of some methods that use bitmasks as an argument wanting a uint in C# instead of an int in the type signature, something that doesn't appear on GDScript-focused documentation as a difference between signed and unsigned ints doesn't exist in GDScript. Due to C# type coercion in most cases this is niche enough that not many people will run into it, but I want to prevent other people running into this wall as well, so I've put a quick note of bitmasks using uint for method overrides in the C# API differences doc.

[paulloz]

Hello, and thank you for your contribution.
This is not something specific to bitmasks, it is a more general thing about the GDScript types not always aligning with C# types (e.g. int in the documentation might mean long in C#, or float might mean double). We are currently working on a dedicated C# documentation. That will IMHO solve this issue, since it'll always refer to the actual C# API types. In the meantime, it's probably fine to add a note somewhere to explain this, but I'm not sure that we need to focus on bitmasks. I'm also not a big fan of wording errors as being "confusing" in our own documentation.

[LemmaEOF]

Makes sense to me! The C# docs will definitely solve the issue. I can look into adding a note directly on things that use uint possibly, but that's a matter for another PR.