Add copy/edit options to chat bubbles

Feature Request

There are currently no copy or edit options available on chat bubbles in the conversation UI.

Expected Behavior

• Copy: Ability to copy the content of a chat message (both user and assistant messages) to the clipboard.
• Edit: Ability to edit a previously sent user prompt and re-submit it.

Use Case

These are standard chat UI affordances that improve usability — copying code snippets or responses without manually selecting text, and editing a prompt to refine a question without retyping it from scratch.