Replace vis with github.com/visjs

[loleg]

This is the frontend library we use for the workflow editor.

[vokhmak]

there is no "visjs" anymore, they’re providing separate projects instead: Network, Graph2d, Graph3d etc. you can find a bunch of different examples (vis Network) in here: https://visjs.github.io/vis-network/examples/

but anyway this library looks much different that the one we're currently using and redoing the workflow page will probably take a lot of time and effort.