Verify `git mv` rename recognition in coverage/diff tooling

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Problem: Whether the coverage/diff tooling correctly treats a moved file as a rename (versus a delete-plus-add, which would wrongly zero out its prior coverage history and could trip the patch-coverage gate on an otherwise-unchanged file) is unverified today — including for the already in-flight queue decomposition work.

Area: ORB / CI tooling

Proposal: Do a small, throwaway test move of a real file and confirm how Codecov and the diff tooling represent it, before any real extraction work in this milestone begins.

Deliverables:

• A documented, verified answer: does a plain git mv read as a rename to the coverage tooling, or does it need to be structured differently (e.g. moved in a commit with no other changes) to be recognized correctly?

Acceptance criteria:

• A real test move is confirmed to either preserve coverage history correctly, or a documented workaround is established for every subsequent phase to follow.

Boundaries:

• This is a one-time verification, not itself a real code move — revert the throwaway test move once the answer is confirmed.

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JSO-3538