Wrong Frame ID for Image Messages

[SwiftGust]

IMPORTANT
Before reporting a new bug make sure you have:

• [V] Checked existing issues https://github.com/ouster-lidar/ouster-ros/issues
• [V] Checked existing discussions https://github.com/ouster-lidar/ouster-ros/discussions
• [V] Checked ouster community https://community.ouster.com/
  If you couldn't find relevant information and you think this is rather a driver
  problem then proceed with bug reporting.

Describe the bug

I think current frame_id set for image processor in ros driver is incorrect,
it should be lidar_frame not pointcloud_frame
where pointcloud processor can transform lidar_frame to sensor_frame after conversion from polar to cartesian frame
However, I don't think image frame cannot be transformed directly in polar coordinate and cannot find such transformation in the code too.
So I think frame_ids for image processors should be in lidar_frame or project image would create some subtle misalignment

ouster-ros/src/os_driver_nodelet.cpp

Lines 186 to 188 in 9711abd

	if (impl::check_token(tokens, "IMG")) {
	processors.push_back(ImageProcessor::create(
	info, tf_bcast.point_cloud_frame_id(),

To Reproduce
Steps to reproduce the behavior (steps below are just an example):

1. Install & build ouster_ros
2. Run ouster ros driver nodelet with image enabled - nothing needs to be changed
3. Inspect image header(rostopic echo /ouster/range_image/header or else)

rostopic echo /ouster/range_image/header
seq: 6122
stamp: 
  secs: 1730362404
  nsecs: 340280549
frame_id: "os_sensor"
---

Platform (please complete the following information):

• Ouster Sensor? OS0 tested but applicable to all
• Ouster Firmware Version? 2.5.3
• ROS version/distro? noetic
• Operating System? Linux Ubuntu 20.04
• Machine Architecture? Tested on x64