[BUG] Agent view shows "esc to return" hint but Esc interrupts the agent instead

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet (closest related: #77286, #16347 — neither matches exactly, see below)
• [x] This is a single bug report
• [x] I am using the latest version of Claude Code

What's Wrong?

When viewing an attached background agent/session, the header shows a hint:

Viewing @<agent-name> · esc to return

Pressing Esc does not return to the previous view (e.g. the agents dashboard / session list). Instead it interrupts the running agent.

This is worse than simply lacking a hint (as described in #77286, which says there is no on-screen indication of the back binding): here the UI actively displays incorrect guidance, so a user follows the hint and gets a surprising result instead of navigation.

Steps to Reproduce

1. Start or attach to a background agent session so the header reads "Viewing @<agent-name> · esc to return"
2. Press Esc
3. Observe: the agent is interrupted, rather than returning to the previous view

Expected Behavior

Either:

• Esc should actually return to the previous view (matching the hint text), or
• The hint text should be corrected to reflect what Esc actually does, with a non-destructive key offered for "go back" (see suggestions in #77286) - although there is already a way back via navigating the list of agents at the bottom of the screen and selecting "main".

Environment Info

• Platform: darwin (macOS)
• Claude Code version: 2.1.233
• Terminal: wezterm 20240203-110809-5046fc22

Screenshot

<img width="904" height="270" alt="Image" src="https://github.com/user-attachments/assets/407737d0-52ff-4313-986d-0ea2636d9c81" />