fix: remove redundant system reminder wrappers

crates/worker/src/feature/builtin/task/mod.rs

@@ -312,8 +312,7 @@ mod tests {
         let SystemItem::TaskReminder { body, .. } = &queued[0] else {
             panic!("unexpected system item: {:?}", queued[0]);
         };
-        assert_eq!(body.matches("<system-reminder>").count(), 1);
-        assert_eq!(body.matches("</system-reminder>").count(), 1);
+        assert!(body.starts_with("Current session steps are listed below."));
         assert!(body.contains("taskid 1"));
         assert!(body.contains("pending"));
         assert!(body.contains("keep going"));
@@ -338,19 +337,17 @@ mod tests {
             panic!("unexpected system item: {:?}", queued[0]);
         };
         assert_eq!(*source, SystemReminderSource::TaskInactivity);
-        assert_eq!(body.matches("<system-reminder>").count(), 1);
-        assert_eq!(body.matches("</system-reminder>").count(), 1);
+        assert!(body.starts_with("Current session steps are listed below."));
         assert!(body.contains("typed"));
     }
 
     #[test]
-    fn render_task_reminder_body_is_unwrapped_for_system_reminder_helper() {
+    fn render_task_reminder_body_is_plain_system_text() {
         let feature = TaskFeature::new();
         let task = feature.task_store().create("body".into(), String::new());
         let body = render_task_reminder_body(&[task]);
 
-        assert!(!body.contains("<system-reminder>"));
-        assert!(!body.contains("</system-reminder>"));
+        assert!(body.starts_with("Current session steps are listed below."));
         assert!(body.contains("TaskUpdate"));
         assert!(body.contains("taskid 1"));
     }