* feat: llms.txt
* feat: split llms.txt into multiple files
We have too many docs, so the concatenated text file uses an unreasonable amount of tokens. Chunk it up a little so it's more usable.
Improve the way docs are indexed and FTS results are ranked, so results are more relevant.
Also improve debouncing and searching UX so it feels a bit faster and you can scan the results more easily.