Debusine command to generate workspace-specific debusine commands

This is a bit of a crazyeative idea.

I noticed that it's quite tedious to specify the workspace on most debusine command, and I thought that we could have debusine generate a python script that's tailored for a workspace, with an easier to use command line.

The idea is to have a debusine workspace cli-interface {workspacename} command that outputs a Python script with most of Debusine commands, except the server, scope and workspace arguments are hardcoded and do not appear as command line arguments.

argcomplete would work with that out of the box.

This would only be marginally useful as such, but the cli-interface command could also introspect the workspace on the server and generate subcomamnds for all configured workflow templates, which would then get their own argcomplete support, and that would start to get interesting.

Since the recent CLI reorganization, with subcommands being implemented as python classes, this should be technically quite doable.