feat(ls): expand design-system tokens + utility classes
Adds to ls.css:
- Spacing scale (--space-1..16, 4px base)
- Radius ladder (--r-xs/sm/md/xl in addition to existing lg/pill)
- Semantic color aliases (--success/warning/danger/info -> existing brand)
- Typography scale (--text-xs..3xl) + font-weight scale (--fw-*)
- Motion tokens (--ease-out, --ease-spring, --duration-*)
- Breakpoint documentation vars
- Utility classes (.hidden, .p-*, .m-*, .gap-*, .flex, .grid, .text-*, .rounded-*)
- Shared .ls-skeleton with shimmer animation
All existing tokens preserved unchanged -- additions only.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Maxim Dolgolyov
dfaa346051