Pressing Enter during long paste sends incomplete message

When pasting a long piece of text into Claude Code, if you press Enter before the paste completes, the message gets sent as soon as the paste finishes - but it sends whatever was in the input at the moment you pressed Enter (the incomplete/partial text), not the full pasted content.

Expected behavior

Either:

• Enter should be ignored while pasting is in progress, OR
• The full pasted content should be sent after paste completes

Steps to reproduce

1. Copy a long piece of text (e.g., 1000+ lines)
2. Paste it into Claude Code
3. While the paste is still in progress (before it completes), press Enter
4. Observe that the message is sent with only partial content

Screenshot

<img width="941" height="758" alt="Image" src="https://github.com/user-attachments/assets/61553ab9-41f9-474c-96ab-3e6a869848f4" />

(Note that in the text box, the original message is still there, but the partial original message is also sent as the previous message.)

Environment

• macOS 15.6.1 (Build 24G90)
• Claude Code 2.0.60
• Terminal: Apple Terminal 455.1
• Shell: zsh