Enable swagger-ui's dark mode support added in
https://github.com/swagger-api/swagger-ui/pull/10653. Background colors
match gitea, link colors match swagger-ui.
Co-authored-by: Claude (Opus 4.6) <noreply@anthropic.com>
Ran most of the Less files through the Less compiler and Prettier and
then followed up with a round of manual fixes.
The Less compiler had unfortunately stripped all `//` style comments
that I had to restore (It did preserve `/* */` comments). Other fixes
include duplicate selector removal which were revealed after the
transpilation and which weren't caught by stylelint before but now are.
Fixes: https://github.com/go-gitea/gitea/issues/15565
