Allow instance admins to add custom CSS that will affect
every page of their instance.
This is done with a new CustomCSS instance setting that
works pretty much exactly like the Users CustomCSS property.
This custom CSS is then requested for every page load.
User styles/themes take precedence over this CSS.
* [chore] Refactor HTML templates and CSS
* eslint
* ignore "Local"
* rss tests
* fiddle with OG just a tiny bit
* dick around with polls a bit more so SR stops saying "clickable"
* remove break
* oh lord
* don't lazy load avatar
* fix ogmeta tests
* clean up some cruft
* catch remaining calls to c.HTML
* fix error rendering + stack overflow in tag
* allow templating attributes
* fix indent
* set aria-hidden on status complementary content, since it's already present in the label anyway
* tidy up templating calls a little
* try to make styling a bit more consistent + readable
* fix up some remaining CSS issues
* fix up reports
* [chore] Remove years from all license headers
Years or year ranges aren't required in license headers. Many projects
have removed them in recent years and it avoids a bit of yearly toil.
In many cases our copyright claim was also a bit dodgy since we added
the 2021-2023 header to files created after 2021 but you can't claim
copyright into the past that way.
* [chore] Add license header check
This ensures a license header is always added to any new file. This
avoids maintainers/reviewers needing to remember to check for and ask
for it in case a contribution doesn't include it.
* [chore] Add missing license headers
* [chore] Further updates to license header
* Use the more common // indentend comment format
* Remove the hack we had for the linter now that we use the // format
* Add SPDX license identifier
