[FEATURE] Visual indicator for which queued message is actively processing

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

When I queue multiple messages while Claude Code is working, the queued-entries list above the input box shows all pending messages with no distinction between "currently being sent as the active turn" and "still waiting." Each queued message runs as its own separate turn, automatically, one after another, but I can't tell from the UI which one is actually in flight at a given moment. This matters when I've queued follow-up instructions that depend on context from an earlier queued message finishing first, since I have no way to confirm where processing actually is.

Proposed Solution

Add a visual marker on the queued-entries list showing which entry is the active turn versus which are still pending, for example a spinner or highlight on the in-progress item and a dimmed/plain style for the rest. Ideally this updates live as each queued message clears and the next one starts.

Alternative Solutions

I currently just wait and watch the transcript scroll to infer progress, or avoid queuing more than one message at a time so there's no ambiguity. Neither is a real fix, it just avoids the problem.

Priority

Medium - Would be very helpful

Feature Category

Interactive mode (TUI)

Use Case Example

1. I ask Claude Code to refactor a module.
2. While it works, I queue two more messages: one asking it to also update the corresponding tests, one asking it to update a doc reference.
3. All three run as separate turns back-to-back with no pause.
4. I want to glance at the queue and know which of the three is currently running, so I know whether it's safe to add a fourth message that depends on the test update having already happened.

Additional Context

Confirmed via the interactive-mode docs (code.claude.com/docs/en/interactive-mode.md) that queued messages are sent one at a time, each as a separate turn, not batched. The only existing control is Up, which pulls all queued messages back into the input box at once. There's no per-message inspect, reorder, or status indicator.