Reworks search to not be a page and instead to be inline dropdown.
<img width="763" alt="Screenshot 2024-02-05 at 13 22 58"
src="https://github.com/tldraw/tldraw/assets/469604/4e5a8076-62cd-44bb-b8e7-7f5ecdc4af24">
- rework search completely
- rm Search Results css
- uses Ariakit and add appropriate hooks / styling
- I couldn't use Radix unfortunately since they're still working on
adding a Combox: https://github.com/radix-ui/primitives/issues/1342
- I'm open to other suggestions but Ariakit plays nicely with Radix and
keeps things open to migrate to Radix in the future
- fixes bug with not scrolling to right place when having a direct link
- adds categories in the search results - examples / reference / learn
- and adds category icons. Let me know if there's a better policy for
adding new SVG icons cc @steveruizok
### Change Type
- [x] `minor` — New feature
### Test Plan
1. Test searches using normal method for each type (examples, docs,
refs)
2. Test searches using AI for each type (ditto)
### Release Notes
- Docs: rework the search to be an inline dropdown.
