Manage httpd and node

[JChrist]

Our plugin requires radicle-httpd and radicle-node to be running, so that it can load all necessary information from it for project(s), patches and issues (httpd) and sync changes with remote(s) (node).
However, the current DX is not quite good and we expect users to manually start these.

We can improve upon this, by adding some kind of management interface for the node and the httpd, offering a way to start/stop/restart them and possibly show logs.

Optionally, we could examine automatically starting them, and possibly stopping them when the IDE shuts down.