Dependency cleanup

[wherget]

This PR tries to minimize dependencies needing to be shipped to reduce the size of the nupkg.

I'd like to highlight that:

• DiaSymReader isn't needed (anymore), which alleviates the need for the Azure nuget repository
• It can be easily replaced by on of its direct dependencies (System.Reflection.Metadata), whose version that was previously used indirectly had been deprecated. Bumped to a current-ish release.
• It should be enough to build the CodeGen Part of the Netcode Editor package, Editor custom components are of little use to us here.

Caveats:

• I'm not sure how well the DEVELOPMENT_BUILD define for the Netcode library holds up across versions. It did for all 2-ish that I tested
• I've not actually checked across the entirety of the matrix build locally if "it compiles" implies "it works". 😅