fix resolution profile not applied in ros_topic_converter

[penguin1q]

When using ros_topic_converter with a non-zero resolution, the resolution
parameter had no effect on the compressed output. This happened because
encoding_info was computed before applyResolutionProfile() modified
pc_info.fields, so the compression remained effectively reversible even
when a non-zero resolution was specified.

This PR applies the resolution profile before computing encoding_info,
so encoding_info reflects the updated field resolutions.

Changes

Before:

const auto encoding_info = cloudini_ros::toEncodingInfo(pc_info);
cloudini_ros::applyResolutionProfile(cloudini_ros::ResolutionProfile{}, pc_info.fields, resolution_);
cloudini_ros::convertPointCloud2ToCompressedCloud(pc_info, encoding_info, output_raw_message_);

After:

cloudini_ros::applyResolutionProfile(cloudini_ros::ResolutionProfile{}, pc_info.fields, resolution_);
const auto encoding_info = cloudini_ros::toEncodingInfo(pc_info);
cloudini_ros::convertPointCloud2ToCompressedCloud(pc_info, encoding_info, output_raw_message_);

Testing

• ROS2 Humble
• Input data: KITTI dataset converted to rosbag2
• Tested resolution = 0.001 (default) and resolution = 0.01

Before this patch:

• resolution parameter had no visible effect
• output remained reversible

After this patch:

• resolution affects compression as expected
• output is no longer reversible for non-zero resolution, as intended