Fix On Newer Loom

[TheBrokenRail]

genSourcesDecompile was merged with genSources.

[TheBrokenRail]

I have changed the Weft build process so it no longer converts from intermediary -> official, I did this originally for debugging, but I think it makes more sense anyways. Since it is guaranteed for the official mappings to change from 1.16.2-pre1 to 1.16.2-pre2 for instance, while the intermediary mapping will most likely stay the same. It also heavily simplifies the Weft build process. If you would like this change reverted I would be happy to, but IMO converting to official just doesn't make that much sense form what I know.

[Daomephsta]

Don't make multiple unrelated changes in one PR. Each unrelated change should be its own PR.
Also don't make PRs with no description unless the title is wholly sufficient. In this case you should have detailed what the breaking changes in newer Loom are.
These apply to any project on any PR-supporting Git host.

With regards to the build process changes, I'm not interested in those. Weft is due to be merged with Yarn, and Warp with Loom.
That'll involve a large rewrite anyway, because the way Warp externally hooks into Loom is a bit of a hack.