Description

This PR makes the changes necessary to support the new Nebula single-node architecture.
These changes can be summarized as:

• merge the separate Nebula nodes into one in the launch file
• find and read default sensor config file in case none is specified. Parameters specified as arguments will override the values in the file

⚠️ This PR has to be merged in a coordinated manner with the corresponding PRs listed below. The timeline is currently being discussed.

Related links

Internal Tickets:

• TIER IV internal link -- parent issue
• TIER IV internal link -- this issue

Depends on:

• chore(autoware.repos): add ros2_socketcan and change transport_drivers fork autoware#5008
• chore: merge nebula/develop tier4/nebula#176

How was this PR tested?

• TBA

Notes for reviewers

None.

Interface changes

None.

Effects on system behavior

Nebula should experience less packet loss & other issues. The hardware monitor is now launched when launch_driver is true (was not launched at all before). No other behavioral changes expected.

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Post-review checklist for the PR author

The PR author must check the checkboxes below before merging.

• There are no open discussions or they are tracked via tickets.

After all checkboxes are checked, anyone who has write access can merge the PR.