feat(m): add better UI for creating shortcuts
I've made a few pages to create and delete shortcuts, as well as handle
all of the error and confirmation cases that come out of that.
The templating is rather nasty - I believe it's *safe* but I'm not
certain that it's completely *correct* (i.e. that there are no cases
which mangle a value somewhere). Additionally, I'm unhappy with the
general string rewriting garbage this leads to... there's nothing to
stop, say, double-templating/etc. Probably we need to at minimum do a
regex replace with a function to fetch the replacements properly, but
I think we may be reaching the point where switching to something other
than plain HTML is worth it...
We use the execCommand method for copying rather than
navigator.clipboard because one intention of this is to be accessible at
http://go/ - which isn't a secure context. If that's the case, we can't
copy with navigator.clipboard, but execCommand("copy") will still work.
Yay for web APIs!
Finally, we need UI for listing out shortcuts. That should probably
be next, over even implementing regex shortcuts (despite I really want
to...)