Verify integrity manifest

Re-check SHA-256 integrity of a .dcm + .dcm.sig pair.

Drop a DICOM file and its .dcm.sig integrity manifest. dcmage recomputes the SHA-256 hash of the bytes (and of the embedded audit snapshot) and compares them to the values recorded at export time. A green check means the file is byte-for-byte identical to what was exported; a red cross means it has been modified or corrupted.

Tip The sidecar also contains the full audit trail snapshot captured at the moment of export — use it for chain-of-custody documentation. Caution This is a corruption-detection control, not a cryptographic signature. The manifest is unkeyed, so it does not prove authorship and is not tamper-proof against a deliberate adversary who re-creates the sidecar.