[BUG] Rate limit UI clobbers in-progress text in input field

Description

When the session usage limit is reached while typing a prompt, the /rate-limit-options UI appears and replaces the text that was being composed in the input field. The user loses their in-progress prompt with no way to recover it.

This is tangential to #14129, but the user input clobbering happens whenever /rate-limit-options occurs, not necessarily in a loop.

Steps to reproduce

1. Start typing a prompt in the Claude Code input field
2. Continue using the session until the usage limit is reached mid-typing
3. Observe that the rate limit options UI appears and replaces the input field contents

Expected behavior

The rate limit options UI should preserve the user's in-progress text. After selecting an option (e.g., waiting for the limit to reset), the previously typed text should be restored to the input field.

Actual behavior

The rate limit options UI:

❯ /rate-limit-options 
─────────────────────────────────────────────────────────────────────────────────
 What do you want to do?

 ❯ 1. Stop and wait for limit to reset
   2. Upgrade your plan

replaces the input field, and the text that was being typed is lost.

Environment

• OS: macOS