Extract expert store route handling into dedicated context store

Parent issue: #6254

## Description
Extract the expert store module's route handling into dedicated context store

## Tasks
- [ ] Extract the expert store module's route handling into dedicated context store
- [ ] Will be able to plug in more data for the rag agent to be more contextually aware of the user's context/intent

## Related Issues
- Parent: #6254

Start by locating the expert store module and tracing its route handling, then read parent issue #6254 for the surrounding scope. Done means the route handling is extracted into a dedicated context store that can support additional context data for the RAG agent.

Written by the indexing model from the issue text.