fix(event): rem_recovered as warn with manual restart reminder

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

src/event.rs

@@ -434,9 +434,9 @@ async fn persist_event_if_needed(
         AppEvent::RemRecovered { unit_id } => {
             let code = fetch_unit_code(pool, *unit_id).await;
             Some((
-                "unit.rem_recovered", "info",
+                "unit.rem_recovered", "warn",
                 Some(*unit_id), None, None,
-                format!("单元【{}】已切换回远程控制", code),
+                format!("单元【{}】已切换回远程控制，自动控制需手动重新启动", code),
                 serde_json::json!({ "unit_id": unit_id }),
             ))
         }