feature request: Integrate Crayon UI for convex agents

# feature request

requesting support for [crayon-ui](https://github.com/thesysdev/crayon) in convex agents. If we are able to do something like dynamic UI generation over the convex infra, that would be awesome

thanks

Start by reviewing how this repository structures Convex agents and then examine the linked Crayon UI project. Define the expected dynamic UI integration and its acceptance criteria before estimating implementation work; the issue currently names no files, tests, or entry points.

Written by the indexing model from the issue text.