Provide standard highdicom #454 Frame UID patch with bytewise verification

[lindicaphxag-tech]

One maintainer-native patch, no ClinGeom dependency

This PR stages an actual, conventional unified diff for the pinned highdicom #454 MONAI bridge.

The concrete failure

On the exact public highdicom #454 head 4524bb0b0c8b3141f6f5b26d047b8da43c69e61e, an automatic Volume -> MetaTensor -> Volume round-trip preserves affine numerically (max error 0.0) but drops highdicom's FrameOfReferenceUID. Two Volumes with distinct UIDs but equal affine become indistinguishable in that metadata field; an explicit frame_of_reference_uid argument works.

Patch

Only src/highdicom/volume.py: two insertion sites, no new dependency, no geometry conversion change:

• to_monai() saves a known UID to a namespaced metadata field;
• from_monai() uses it only if caller's explicit UID is None.

Independent evidence

• Existing paired runtime CI already passes on the pinned source with the Python patch script and checks preserved UID/explicit override/legacy metadata/RAS-LPS affine round-trip.
• This PR adds highdicom_454_frame_uid.patch and a separate lightweight CI that checks git apply --check on exact upstream, applies the patch, and byte-compares it with the already-tested Python patch result.
• Full copy/paste application instructions and evidence boundary in HIGHDICOM_454_UPSTREAM_PATCH.md.

Not claimed: an upstream PR, highdicom maintainer approval, independent external adoption or clinical safety. Third-party GitHub mutation remains blocked with HTTP 403; this public patch is staged for human-authenticated upstream submission or reviewer feedback.

This is deliberately a narrow upstream compatibility fix, not a request to adopt the broader ClinGeom research system.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}