Scratch is migrating to a monorepo

[alctd]

Scratch has started migrating multiple repositories to a monorepo. This means if we want the latest updates to Scratch, we are going to have to make a merge between turbowarp and the scratch monorepo, else we are going to be unable to get recent Scratch updates.

@GarboMuffin please start work on this.

[50-scratch-tabs]

I don't think this is a big deal to them, tw is already multiple hundred commits behind Scratch.

[GarboMuffin]

Updating to the monorepo has some extra hidden implications.

Sure we are thousands of commits behind but >90% of those are just all the scratch packages updating each other, not many of those are important