feat(claudbg-e4ac): highlight active agent in sidebar when viewing its transcript

When the user is viewing a SubagentTranscript, the corresponding entry
in the sub-agents panel is now highlighted with '>' prefix regardless
of which panel has keyboard focus.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.beans/claudbg-e4ac--tui-selected-agent-highlights-in-agents-widget-whe.md

@@ -1,10 +1,15 @@
 ---
 # claudbg-e4ac
 title: 'TUI: selected agent highlights in agents widget when viewing agent transcript'
-status: todo
+status: completed
 type: feature
+priority: normal
 created_at: 2026-03-31T23:45:09Z
-updated_at: 2026-03-31T23:45:09Z
+updated_at: 2026-04-01T05:55:52Z
 ---
 
 When an agent transcript is being viewed, the corresponding agent entry in the agents widget panel should be highlighted/selected to show which agent is active.
+
+## Summary of Changes
+
+In `render_transcript` (`src/tui/screens/transcript.rs`), changed the agent highlight condition to check two cases: `is_viewing` (current screen is `SubagentTranscript` with matching `agent_id`) OR `is_panel_selected` (index matches `subagent_selected` and panel has focus). The agent in view is always highlighted regardless of which panel has focus.

src/tui/screens/transcript.rs

@@ -496,7 +496,16 @@ pub fn render_transcript(f: &mut Frame, area: Rect, state: &AppState) {
                     agent.agent_id.clone()
                 };
                 let agent_type = agent.agent_type.as_deref().unwrap_or("agent").to_string();
-                if i == state.subagent_selected && state.focus == Focus::SubagentsPanel {
+                // Highlight when this agent is the one currently being viewed
+                // (SubagentTranscript) OR when it is selected in the panel.
+                let is_viewing = matches!(
+                    &state.screen,
+                    crate::tui::state::Screen::SubagentTranscript { agent_id, .. }
+                        if *agent_id == agent.agent_id
+                );
+                let is_panel_selected =
+                    i == state.subagent_selected && state.focus == Focus::SubagentsPanel;
+                if is_viewing || is_panel_selected {
                     Line::from(Span::styled(
                         format!("> {short_id}  {agent_type}"),
                         Style::default().fg(Color::Yellow),