Hide short worked-for label in final separator (#10452)

- Hide the "Worked for" label in the final message separator unless
elapsed time is over one minute.\n- Update/add tests to cover both
hidden (<60s) and shown (>=61s) behavior.

codex-rs/tui/src/history_cell.rs

@@ -2147,6 +2147,7 @@ impl HistoryCell for FinalMessageSeparator {
         let mut label_parts = Vec::new();
         if let Some(elapsed_seconds) = self
             .elapsed_seconds
+            .filter(|seconds| *seconds > 60)
             .map(super::status_indicator_widget::fmt_elapsed_compact)
         {
             label_parts.push(format!("Worked for {elapsed_seconds}"));
@@ -2358,7 +2359,7 @@ mod tests {
     }
 
     #[test]
-    fn final_message_separator_includes_runtime_metrics() {
+    fn final_message_separator_hides_short_worked_label_and_includes_runtime_metrics() {
         let summary = RuntimeMetricsSummary {
             tool_calls: RuntimeMetricTotals {
                 count: 3,
@@ -2385,7 +2386,7 @@ mod tests {
         let rendered = render_lines(&cell.display_lines(200));
 
         assert_eq!(rendered.len(), 1);
-        assert!(rendered[0].contains("Worked for 12s"));
+        assert!(!rendered[0].contains("Worked for"));
         assert!(rendered[0].contains("Local tools: 3 calls (2.5s)"));
         assert!(rendered[0].contains("Inference: 2 calls (1.2s)"));
         assert!(rendered[0].contains("WebSocket: 1 events send (700ms)"));
@@ -2393,6 +2394,15 @@ mod tests {
         assert!(rendered[0].contains("4 events received (1.2s)"));
     }
 
+    #[test]
+    fn final_message_separator_includes_worked_label_after_one_minute() {
+        let cell = FinalMessageSeparator::new(Some(61), None);
+        let rendered = render_lines(&cell.display_lines(200));
+
+        assert_eq!(rendered.len(), 1);
+        assert!(rendered[0].contains("Worked for"));
+    }
+
     #[test]
     fn ps_output_empty_snapshot() {
         let cell = new_unified_exec_processes_output(Vec::new());