Add image thumbnail preview when pasting images

When pasting images into Claude Code, there's no visual feedback or thumbnail preview showing what was pasted. This makes it difficult to confirm you've pasted the correct image before sending.

Current behavior: Image is pasted with no visual indication of its content.

Expected behavior: Show a small thumbnail or preview of the pasted image so the user can verify it's the correct one before submitting.

(sent from claude code)