Merge the separate "Support native host styling using CSS variables" and
"Reacting to light/dark theme changes" sections into a single "Matching
host styling (CSS variables, theme, and fonts)" pattern. This provides
clearer guidance by covering all three concerns together.
- Rename `docs/patterns.ts` to `docs/patterns.tsx` for JSX support
- Add `hostStylingVanillaJs` and `hostStylingReact` consolidated examples
- Enhance `applyHostFonts_fromHostContext` to apply initial fonts after
`connect()`, not just on context change
- Add CSS usage examples to `applyHostStyleVariables()` JSDoc
- Update font example to use `var(--font-sans, system-ui, sans-serif)`
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>