GNCPs and SNCPs will always save incorrectly due to fixed header name

[NextinMono]

In this snippet of code:

SharpNeedle/Source/SharpNeedle/Framework/Ninja/Csd/CsdProject.cs

Lines 96 to 106 in aec8d42

	void CreatePackageFile(IChunk chunk)
	{
	using Stream stream = Package.GetStream(Package.Add(), true, true);
	using BinaryObjectWriter infoWriter = new(stream, StreamOwnership.Retain, Endianness);
	InfoChunk info = new()
	{
	Signature = BinaryHelper.MakeSignature<uint>(Endianness == Endianness.Little ? "NXIF" : "NYIF"),
	};
	info.Chunks.Add(chunk);
	infoWriter.WriteObject(info);
	}

The writer always assumes that the header of the chunk should be "NXIF" and "NYIF". However, GNCP and SNCP files use different names ("NGIF" and "NSIF") which means that GNCP and SNCP files will load and save, but will cause issues in-game.