* Improve getting started Coder CTA
This wasn't very standout-ish before, and I think it's
wise for us to experiment with directing users to Coder.
* Update nix flake
* Update diff
* Add advert to code-server install
* Fix patch to reset columns if getting started is disabled
* Update text for advert
I took our website's SVG favicon and plopped it on a round
white rectangle in Affinity Designer. The I exported it as an SVG and
wrote a script that uses imagemagick to convert to the various sizes and
formats we need.
Closes#2307
Might fix#1181, although not for the reasons I initially
thought (because the URLs are resolved from the manifest path, not the
path of the current page). This should ensure that the URLs used by the
manifest are always correct regardless of the manifest's path.
