feat(autoware_perception_msgs): add instance segmentation msg

[StepTurtle]

Description

Move autowarefoundation/autoware_internal_msgs#23 here after last conversations.

Add a new message type to send instance segmentation results.

Related links

Parent Issue:

• Implement RTMDet to Perception Pipeline autoware.universe#7235

Discussion:

• https://github.com/orgs/autowarefoundation/discussions/5047

Parent PR:

• feat(autoware_tensorrt_rtmdet): add tensorrt rtmdet model autoware.universe#8165

How was this PR tested?

Notes for reviewers

None.

Effects on system behavior

None.

[github-actions]

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[mitsudome-r]

Let me check with Fatih on this during today's Software WG call.
autowarefoundation/autoware_internal_msgs#23 (comment)

[StepTurtle]

New msg is added with this PR to autoware_internal_perception_msgs

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 0.00%. Comparing base (c246607) to head (a27f1e8).
Report is 4 commits behind head on main.

Additional details and impacted files

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  Coverage   0.00%      0              
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  Files        615      0     -615     
  Lines      30613      0   -30613     
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+ Misses     30613      0   -30613     

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