Previously, we forgot to associate the `Markdown` entity to `MarkdownElement` during `prepaint`. This caused calls to `Context<Markdown>::notify` to not invalidate the view cache, which meant we would have to wait for some other invalidation before seeing the results of that initial notify. Release Notes: - Improved responsiveness of mouse interactions with the agent panel. Co-authored-by: Ben Brandt <benjamin.j.brandt@gmail.com>