Remove autoware_utils package

[isamu-takagi]

Checklist

• I've read the contribution guidelines.
• I've searched other issues and no duplicate issues were found.
• I've agreed with the maintainers that I can plan this task.

Description

Task #34 split autoware_utils into packages for each feature. Therefore autoware_utils is now deprecated and we recommend using the separate packages instead.

Purpose

Remove the packages that cause unnecessary dependencies.

Possible approaches

• [tentative] 2025-06-01: autoware_utils headers will display the message
• [tentative] 2025-07-01: autoware_utils namespace will be deprecated.
• [tentative] 2025-08-01: autoware_utils package will be removed

Definition of done

• display message
• deprecate namespace
• remove package

[esteve]

@isamu-takagi according to https://index.ros.org/p/autoware_utils/#humble-deps, autoware_lanelet2_extension is the only downstream dependency that's been released onto the ROS buildfarm. It'd be good to make a new release of autoware_lanelet2_extension that uses the specialized autoware_utils projects.

[isamu-takagi]

@esteve
I hear that @soblin -san is trying to remove the dependency from autoware_lanelet2_extension.
autowarefoundation/autoware_lanelet2_extension#47