DX for Github Actions generator

[visual raptor]

yeah that's a good question. The initial version actually used the official action. It just felt like it would be simpler to remove it, and so far it hasn't affected the DX. But it can easily be brought back if needed.

the important change, really, is that the DX is now purely on the Dagger side. The YAML becomes like a compiled artifact. You never have to touch it unless you're debugging the compiler itself. Just like sometimes you have to decompile a binary. But 99% of the time, you just run it.

TLDR: with this pattern the generated YAML config becomes a binary