Add shortcut to cancel queued message without interrupting current response

Problem

When Claude is mid-response and I type a follow-up message and hit Enter, the message gets queued. If I realize the message is stale or wrong, there's no way to discard it without also interrupting Claude's current work.

• Escape before Enter discards input — works fine
• Escape/Ctrl+C after Enter stops everything — the queued message AND Claude's response

Request

A separate shortcut (e.g. Ctrl+Z or similar) that cancels the queued message but lets Claude finish its current response. "Cancel what I just sent" should be distinct from "stop the AI."

Why it matters

In long-running tool calls or multi-step responses, the queue delay can be several minutes. By the time Claude reads the queued message, it's no longer relevant. The only option is to interrupt and lose Claude's in-progress work, or let a stale message through and deal with the confusion.