ROS: Fix controller placeholder quaternion

[sgrizan-nv]

Use XYZW identity ordering for missing controller orientation fields so placeholder payloads match the rest of the ROS pose conventions.

Summary by CodeRabbit

• Bug Fixes
  • Corrected default controller orientation values when a controller input is unavailable.

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ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between 37d3345 and 344ad01.

📒 Files selected for processing (1)

• examples/teleop_ros2/python/messages.py

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📝 Walkthrough

Walkthrough

This PR modifies a single line in examples/teleop_ros2/python/messages.py. The _as_quat helper function, which provides fallback quaternion values when controller input is absent, changes its default quaternion constant from [1.0, 0.0, 0.0, 0.0] to [0.0, 0.0, 0.0, 1.0]. Both representations correspond to identity rotations but differ in quaternion component ordering convention (scalar-first vs. scalar-last). This affects the default orientation fields emitted in the controller payload when input is missing.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and specifically describes the main change: fixing the quaternion used as a placeholder for missing controller orientation fields from WXYZ to XYZW ordering.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

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• Commit unit tests in branch sgrizan/branch5

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