Update `global.css` in all `basic-server-*` examples (and `integration-server`
for consistency) to better serve as templates for AI coding agents scaffolding
new MCP Apps.
Changes:
- Use CSS custom properties (`--font-sans`, `--color-text-primary`, etc.) with
sensible fallbacks, enabling host design system integration
- Add `color-scheme: light dark` and `light-dark()` fallbacks for theme support
- Include comprehensive typography: h1-h6, body text, `code`/`pre`/`kbd`, `b`/`strong`
- Move `#server-time` styles from global CSS to component stylesheets (classes
instead of IDs for better CSS practices)
Updates E2E test selectors in `DYNAMIC_MASKS` to match the new class-based
selectors.
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>