Add point cloud decimation parameters and services to documentation

docs/zh/source/4_application_guide/launch_parameters.md

@@ -41,6 +41,8 @@
     *   启用左红外图像传输插件。默认值：`["image_transport/compressed", "image_transport/raw", "image_transport/theora"]`。
 *   **`right_ir.image_raw.enable_pub_plugins`**
     *   启用右红外图像传输插件。默认值：`["image_transport/compressed", "image_transport/raw", "image_transport/theora"]`。
+*   **`point_cloud_decimation_filter_factor`**
+    *   点云下采样因子。范围：`1–8`，`1`表示不下采样，数值越大下采样越强。
 
 ### 传感器控制
 

docs/zh/source/4_application_guide/services.md

@@ -256,3 +256,13 @@
                     -6.804073229432106e-06]}'
     ros2 service call /camera/get_user_calib_params orbbec_camera_msgs/srv/GetUserCalibParams '{}'
     ```
+
+### 点云下采样
+*   `/camera/set_point_cloud_decimation`
+    ```bash
+    ros2 service call /camera/set_point_cloud_decimation orbbec_camera_msgs/srv/SetInt32 '{data: 8}'
+    ```
+*   `/camera/get_point_cloud_decimation`
+    ```bash
+    ros2 service call /camera/get_point_cloud_decimation orbbec_camera_msgs/srv/GetInt32 '{}'
+    ```