Switch to PNPM

[dukio]

It's faster 🚀

+bonus

• Now when running pnpm dev it will automatically check that you have the correct dependencies installed (no more need to npm ci when checking out a PR or after pulling commits!)

This is now possible because it's simply so fast you won't even notice it ...and it doesn't randomly break like with npm i

[dukio]

@WarpWing can you tell me what should be done to the Dockerfile so it works with pnpm? (I have no clue how to do/test it)

[WarpWing]

Every time the majority of devs approve a PR but doesn't merge it, a kitten gets killed and it's their collective fault.