[BUG] Status line stuck on 'Computing...' after response completes, Escape has no effect

Description

After a response fully completes (the '● Done.' bullet is visible), the status line remains stuck showing 'Computing... (Xm Ys · XXX.Xk tokens)'. The UI shows the response is done but the status line never clears. Pressing Escape repeatedly has no effect.

Screenshot

The status line shows:

● Done.

* Computing… (1m 10s · 207.4k tokens)

The green '● Done.' bullet confirms the response is complete. The red '* Computing…' line should have cleared but did not.

Steps to Reproduce

1. Run a long multi-step session (agents, background tasks, etc.)
2. Response completes — '● Done.' appears
3. Status line remains on 'Computing...' indefinitely
4. Press Escape — no effect
5. The UI appears functional but the status indicator is permanently stuck until the next message is sent

Expected Behavior

Status line should clear and return to idle state when the response is complete.

Actual Behavior

Status line stays on 'Computing...' with the elapsed time and token count from the completed response. Escape does not clear it.

Environment

• Platform: macOS 25.3.0
• Model: claude-sonnet-4-6
• Session involved: multi-agent team coordination with background tasks

Related

Similar to #20171 ('Generating...' stuck on Windows) but distinct: this is macOS, the trigger is response completion rather than mid-task hang, and the status verb is 'Computing...' rather than 'Generating...'.