2297: Feat(Search): Enhance formating search results r=ManyTheFish a=ManyTheFish
Add new settings and change crop_len behavior to count words instead of characters.
- [x] `highlightPreTag`
- [x] `highlightPostTag`
- [x] `cropMarker`
- [x] `cropLength` count word instead of chars
- [x] `cropLength` 0 is now considered as no `cropLength`
- [ ] ~smart crop finding the best matches interval~ (postponed)
Partially fixes #2214. (no smart crop)
Co-authored-by: ManyTheFish <many@meilisearch.com>