v0.12.0

Comonicon v0.12.0

Diff since v0.11.7

Move all the components back into the same repo, given Comonicon itself only needs 0.01s to load,
Move ComoniconTestUtils to the same repo for convenience, future extensions will be in the lib folder
too.

Rewrite the build system to make use of PackageCompiler 2.0 and a few other bug fixs

Closed issues:

• Error when building (#150)

Merged pull requests:

• rework the package (#152) (@Roger-luo)
• CompatHelper: add new compat entry for "Scratch" at version "1.1" (#155) (@github-actions[bot])
• support shell installation (#156) (@Roger-luo)