Copy icon on a response should include images, not just text

## Description

Each response in the Claude Code desktop app has a "Copy" icon (leftmost icon at the bottom of the response) that copies the response's text to the clipboard. When a response includes inline images (e.g., screenshots from computer-use, rendered charts, etc.), those images are not included in the copy — only the text.

## Feature request

Allow the "Copy" icon to copy both the text and any inline images shown in that response, so pasting into a rich-text destination (Notes, Mail, Word, Google Docs, Slack, etc.) preserves the images alongside the text, similar to what a manual click-drag selection + Cmd+C already does.

## Current workaround

Manually click-drag to select the response text and image(s), then Cmd+C, then paste into a rich-text-capable destination. This works, but is more cumbersome than using the dedicated Copy icon, and isn't discoverable.

## Why this matters

Users who want to save or share a record of an agent's work (e.g., text summary of operations performed plus screenshots/figures) currently can't do this with the one-click Copy icon and have to fall back to manual selection.

No file, test, or entry point is named. Start by locating the response Copy icon in the Claude Code desktop app and trace its clipboard behavior; done means copying a response preserves its text and inline images when pasted into a rich-text destination.

Written by the indexing model from the issue text.