Split parts with FoundationNetworking dependency into its own library

[guoye-zhang]

Resolves #76

[ekinnear]

Worth looking into the FoundationEssentials option

[guoye-zhang]

FoundationEssentials is a concept in SwiftFoundation, not the compiler built-in Foundation. Not sure if it requires bringing in another package.

[weissi]

Thanks so much!

[guoye-zhang]

I can't merge this PR due to several checks failing, but I think these are expected to fail

[Lukasa]

Yeah, they're expected to fail. Can you update the readme to clarify that we want users to depend on a range? You want to say something like this:

Swift HTTP Types 2.0.0 was released in December 2024. The only breaking change between Swift HTTP Types 2.0.0 and 1.0.0 was moving a small number of values from HTTPTypesFoundation into a new module, HTTPTypesFoundationNetworking. For any users not affected by this change, it's safe to depend on either the 1.0.0 or 2.0.0 series of releases.

To do so, please use the following dependency in your Package.swift:

.package(url: "https://github.com/apple/swift-http-types.git", "1.0.0" ..< "3.0.0"),