Manual backport of #1243 to gz-rendering9(Close #1248)

[XINJIANGMO]

Closes #1248

Summary

This is a manual backport of #1243 to the gz-rendering9 branch.
The conflict occurred because the main branch includes GZ_PROFILE performance profiling macros which do not exist in the gz-rendering9 branch.

delete macro

Test it

Same as the original PR #1243. You can compile the branch and verify that Update() handles the existing renderable properly without duplicate lines.

Checklist

• Signed all commits for DCO
• Added a screen capture or video to the PR description that demonstrates the feature
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• Updated Bazel files (if adding new files). Created an issue otherwise.
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.
Backports: If this is a backport, please use Rebase and Merge instead.

[Copilot]

Pull request overview

Manual backport of the fix from #1243/#1248 to prevent Ogre2FrustumVisual::Update() from repeatedly creating and attaching new line renderables, which caused duplicated frustum ray lines over time.

Changes:

• Reuse the existing Ogre2DynamicRenderable when present instead of always creating a new one.
• Clear the existing renderable before re-populating points during Update().

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