The javascript is too damn big!

[Floppy]

We need to split up the javascript rather than having a single application bundle.

Some bits are big, and used only in very specific circumstances:

• zxcvbn (this is the big offender)
• uppy / tus_client
• altcha (small, but only ever used on signup)

Some bits can be removed:

• rails-ujs is no longer necessary (but that needs testing on removal)

Some bits are duplicated:

• three.js duplicated inside the offscreen renderer webworker 3MF loader

The rest is small enough or common enough that it can stay in one bundle.