Split WORKSPACE from DOJO

[zardus]

PR #533 got me thinking about this idea that's been bouncing around for a while:

The DOJO infra is really two things: the hosted workspace with all the tooling, novnc, vscode, etc. and the dojo/module/challenge/scoreboard/user stuff. These two things live together right now, but they don't have to (and maybe shouldn't).

For example, we could split out the current dojo into two things:

• the dojo, which handles tracking dojos, solves, etc
• the workspace, which handles starting containers, populating them with files, etc.

The workspace would have an API work launching ephemeral workspace instances, not bound to a challenge, with all data specified via REST/docker. Something like:

• backend API for launching the workspace, returns an access token
• frontend API for accessing the launched workspace

Use cases:

• splitting out our backend from our frontend, for better scaling, isolation, etc
• providing (free) workspaces for community resources such as wargame platforms, including completely static sites like collections of chals on github

We had a discussion on this at the pwn.college hackathon, and IIRC someone had an argument that I'm just describing a docker socket here, but I still feel this is a bit more (e.g., a docker socket can't allow static github repos or something like cryptohack or pwnable.tw --- just examples; no idea if they'd even be interested --- to have a "launch in pwn.college" button).

Opening this issue so the idea doesn't get lost in the ether.