Fix sensecap watcher inference (#1501)

* feat: add keepalive check for Himax client and handle restart

* fix: adjust layout and positioning for top and bottom bars

* fix: fix other param restoring default ​​when modifying one param .

main/boards/sensecap-watcher/sscma_camera.h

@@ -54,6 +54,7 @@ private:
     int detect_invoke_interval_sec = 8; // 默认15秒冷却期，避免频繁开始会话
     int detect_debounce_sec = 1; // 验证期间人员离开的去抖动时间1秒
     int inference_en = 0; // 推理使能开关（0: 关闭, 1: 开启）
+    bool sscma_restarted_ = false;
     
     sscma_client_model_t *model;
     int model_class_cnt = 0;