feat(autoware_carla_interface): add light weight sensor config

[mitsudome-r]

Description

Adds an optional light-weight sensor configuration for autoware_carla_interface to make CARLA simulation usable on machines with limited GPU/CPU resources.

• New use_light_weight_sensor_mapping launch argument (default False). When True, the launch file selects config/sensor_mapping_light_weight.yaml and skips the image_transport republish nodes for the disabled cameras and the multi_camera_combiner node.
• The light-weight mapping uses a single front camera (CAM_FRONT, 120° FOV, 1080x720) instead of the default 6-camera 360° setup, and lowers LiDAR/camera frequency to 10 Hz. LiDAR/IMU/GNSS configuration is otherwise unchanged.
• README updated with a new "Light-Weight Sensor Mapping" subsection and parameter table entries.
• SensorKitLoader now logs a warning when it falls back to the source-tree default sensor mapping path, to make the fallback visible during debugging.

Related links

Parent Issue:

• Add carla docker compose demo script autoware#7079

How was this PR tested?

• Launched e2e_simulator.launch.xml with simulator_type:=carla and use_light_weight_sensor_mapping:=True, confirmed only CAM_FRONT is published and multi_camera_combiner is not started.
• Launched the same with use_light_weight_sensor_mapping:=False (default) and confirmed all 6 cameras and the combiner still come up as before.
• Verified LiDAR, IMU, and GNSS topics are published in both modes.

Notes for reviewers

The default behavior is unchanged — use_light_weight_sensor_mapping defaults to False and the existing sensor_mapping.yaml is selected. Reviewers who don't use the flag should see no functional difference.

Interface changes

None.

Effects on system behavior

None.

[github-actions]

Thank you for contributing to the Autoware project!

🚧 If your pull request is in progress, switch it to draft mode.

Please ensure:

• You've checked our contribution guidelines.
• Your PR follows our pull request guidelines.
• All required CI checks pass before marking the PR ready for review.

[maxime-clem]

Tested with both use_light_weight_sensor_mapping:=False and use_light_weight_sensor_mapping:=True and in both cases Autoware could correctly localize.