Support pasting a copied file (not just drag-and-drop) as an attachment in chat

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Currently, dragging a file into the chat input attaches it as a file reference. However, copying a file (e.g., in Finder/Explorer with Cmd+C / Ctrl+C) and then pasting it into the chat input does not attach the file — it either does nothing or pastes unrelated clipboard text.

Environment: VSCode extension (Claude Code)

Proposed Solution

Expected behavior: Pasting a copied file into the chat input should attach it the same way drag-and-drop does, since both actions represent the same user intent (attaching a file to the conversation).

Alternative Solutions

_No response_

Priority

Critical - Blocking my work

Feature Category

CLI commands and flags

Use Case Example

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Additional Context

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