enhance(ros2agnocast): avoid unnecessary get_topic_names_and_types in topic info_agnocast

[Koichi98]

Description

Optimize ros2 topic info_agnocast by removing the expensive get_topic_names_and_types() call that fetched all topics just to look up the type of a single topic.

Problem

The command made 3 ROS2 API calls:

1. get_topic_names_and_types() — fetched all topics to find the type of the target topic
2. get_publishers_info_by_topic() — called inside print_publishers_info
3. get_subscriptions_info_by_topic() — called inside print_subscribers_info

Change

• Remove get_topic_names_and_types() entirely
• Call get_publishers_info_by_topic() and get_subscriptions_info_by_topic() once in main, extract the topic type from the results, and pass them to the print functions
• ROS2 API calls reduced from 3 to 2, and the most expensive one (full topic discovery) is eliminated

Related links

How was this PR tested?

• Autoware (required)
• bash scripts/test/e2e_test_1to1.bash (required)
• bash scripts/test/e2e_test_2to2.bash (required)
• kunit tests (required when modifying the kernel module)
• bash scripts/test/run_requires_kernel_module_tests.bash (required)
• sample application

Notes for reviewers

Version Update Label (Required)

Please add exactly one of the following labels to this PR:

• need-major-update: User API breaking changes
• need-minor-update: Internal API breaking changes (heaphook/kmod/agnocastlib compatibility)
• need-patch-update: Bug fixes and other changes

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  • Example: fix(foo)[needs major version update]: bar or feat(baz)[needs minor version update]: qux
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