Build a WebGL or WebGPU visualization toolkit for es-membrane v2

Original idea: #183

Lately I've been working on [es-search-references](https://github.com/ajvincent/es-search-references) for visualizing a 2-D graph of references. Part of that has been to use [`@dagrejs/dagre`](https://github.com/dagrejs/dagre/wiki) and its component `graphlib` to create a graph layout.

Looking down the z-axis of my 3-D graph model, I can create an union of my nodes in 2-D, and apply the necessary edges there. Then I can build the 3-D graph (`z="200"`, etc.) from the 2-D layout graph.

As long as I can feed this tool a compatible `Membrane` instance and a starting node, the rest should be very much like my previous work.

Project name: `webgl-membrane-graph`, with an accompanying docs directory.