Begin QMJ Writer

[OroArmor]

This will allow people to make tools to convert fabric projects into quilt projects without needing to re-implement the whole QMJ spec

[AlexIIL]

I'm somewhat conflicted about this - I agree that this functionality is useful (and needed), but unhappy about adding apis to internal packages. I can understand that there isn't really a better place for this though - it's only intended to be used by external tools that will already have to use internal code like org.quiltmc.loader.impl.metadata.FabricModMetadataReader and some related classes.

Overall the code is reasonable, with a couple of major problems:

• Reflection shouldn't be used to access specific fields or classes inside the same project - especially if access can be made package-private. Alternately the getIcon method could be made optional methods in InternalModMetadata, Icons, and FabricLoaderModMetadata.
• Version ranges as arrays are deprecated by the QMJ spec, in preference of explicit all/any specifiers. I've included some code which hopefully fixes this?

[OroArmor]

I'm somewhat conflicted about this - I agree that this functionality is useful (and needed), but unhappy about adding apis to internal packages. I can understand that there isn't really a better place for this though - it's only intended to be used by external tools that will already have to use internal code like org.quiltmc.loader.impl.metadata.FabricModMetadataReader and some related classes.

Yeah that's the problem. It both needs to be "API" but also not. It probably wont get run when loader is actually running, its just something that a tool can use when compiled against loader.