error pages render shop-themed layout but were loading admin.css,
which has no shop component styles. switch to shop.css.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
add system font stack to admin reset CSS so setup/admin pages render
sans-serif on all devices instead of falling through to browser default.
pass path_resolver to CSSGenerator.generate on cache miss paths so
font URLs resolve to digested paths in production.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>