Search engines: add semi-independent engine Neeva
Chore: fix header whitespace
CSS: a11y: brighten bkg for astigmatic readers

Reduces the "halo" effect that comes with reading bright text on a solid
black background.
Fix: use HTTPS links where possible
Update search engines

- Remove goo.ne.jp since it uses Google
- Create "Graveyard" section and move wbsrch to it 🪦
- Restore link to Crawlson since it's back up
Update webhint
Clarify attributions
Add footer heading
Web best practices: add "security" section

Add information on restricting site functionality.

Add some details on accomodating Tor users.
Fix makefiles
Fix 512px favicon
Update "about" page: age, anime faves

According to multiple sources, Seirdy apparently turned 21 a while ago.
Also added an entry to anime fave list.

Rephrase statement on Matrix availability.
Update lighthouserc
Makefile: compress missed assets
Web best practices: dark themes: Mention OLEDs

OLED displays use less energy when displaying darker colors.
Web best practices: async decode + fingerprinting

- Mention image async decoding
- Describe how width-selector use can enable JS-free viewport
Update tooling
Re-add fake favicon.ico

Useful for stuff like the RSS feed.
Picture shortcode: support JPEG-XL, async decoding
Search engines: remove dead link to burf.co