* start html head refactor
this is a bit of a doozy tbh and will probably take a while. the templates are very highly duplicated but not duplicated enough to be an easy little thing
oh well, so it goes.
* some easier html head ones
* add chat, html_head, sign_up_failed_ref, sign_up, submit
* CSP: put it in const.py instead of this weird thing we did before
* fix syntax error
* better call the actual macros
* fix prev commit
* import into settings2
* fix prev commit
* set CSP properly if localhost
* some title fixes i think
* login page
* fix prev commit
* hacky thing to get titles to work i think
* {{stylesheets()}}
* fix prev commit
* title stuff
* cries uncontrollably
* submission fixes i think
* fix prev commit i think
* submission fixes ekfjdhfkdjf
* submission fixes 4
* this may fix submissions idk tbh
* default template: make it a little better on post pages
* default template: some efficiency
A tacit assumption in many parts of the emoji code is that valid
emoji end with .webp. This has led to some absurdities like GIFs with
.webp extensions. However, here we run `gif2webp` over the GIF, which
also reduces its size substantially.