why use elasticsearch, And Support Other AI Model ?

### What would you like to be added?

1. why use es , can drop it
2. can use other ai model

### Why is this needed?

i want to use it

The issue does not identify files, tests, or entry points. Start by locating where Elasticsearch and the current AI model are configured, then determine the scope of removing Elasticsearch and supporting other AI models. Done would require an agreed design and verified support for the requested alternatives.

Written by the indexing model from the issue text.