Uses sandpack in all places so we can do richer code snippets.
Also, drive-by fix to fix sidebar logic.
Also, drive-by fix to hide keyboard hint (Cmd+K) for search on mobile.
### Change Type
- [x] `documentation` — Changes to the documentation only[^2]
### Release Notes
- Docs: reworks code snippets
This PR adds the docs app back into the tldraw monorepo.
## Deploying
We'll want to update our deploy script to update the SOURCE_SHA to the
newest release sha... and then deploy the docs pulling api.json files
from that release. We _could_ update the docs on every push to main, but
we don't have to unless something has changed. Right now there's no
automated deployments from this repo.
## Side effects
To make this one work, I needed to update the lock file. This might be
ok (new year new lock file), and everything builds as expected, though
we may want to spend some time with our scripts to be sure that things
are all good.
I also updated our prettier installation, which decided to add trailing
commas to every generic type. Which is, I suppose, [correct
behavior](https://github.com/prettier/prettier-vscode/issues/955)? But
that caused diffs in every file, which is unfortunate.
### Change Type
- [x] `internal` — Any other changes that don't affect the published
package[^2]
