Highlights for exceptions

[bitjson]

Currently only success states are visually highlighted:

https://github.com/bitjson/bitauth-ide/blob/a2732ef59620511ca0cb02e2d468b01631225a7a/src/editor/editor-types.ts#L81-L98

It would be good if we could provide other highlights for things like "non-standard", "dirty stack", etc. (Unfortunately, these are network specific things too, so we need to figure out how to abstract that properly.)