feat: add CrabQL announcement banner and product section (#16)

## Summary
- Add top announcement banner for upcoming CrabQL product (static
analysis / code integrity platform)
- Add dedicated CrabQL section with product description, feature list,
and syntax-highlighted query preview
- Remove buzzword bingo feature (button, CSS, and JS)

## Test plan
- [ ] Verify announcement banner renders at top of page with
smooth-scroll link to `#crabql`
- [ ] Verify CrabQL section renders with two-column layout (info + code
preview)
- [ ] Verify responsive behavior on mobile (single column, no layout
breaks)
- [ ] Verify buzzword bingo button and all related functionality is
fully removed
- [ ] Verify crab mood widget still works without bingo mood reference

cc @MrFlounder

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Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: mldangelo