A single normalized signature pulled off a chart's raw_document, regardless of the source EMR.
raw preserves the original entry (or the slice we read it from) for transparency/debugging.
signedAt is normalized to a real instant (UTC ISO) by extractEmrSignatures when it can
be parsed; per-EMR extractors populate it with the raw EMR date string and leave normalization to
the central extractor.
A single normalized signature pulled off a chart's
raw_document, regardless of the source EMR.rawpreserves the original entry (or the slice we read it from) for transparency/debugging.signedAtis normalized to a real instant (UTC ISO) by extractEmrSignatures when it can be parsed; per-EMR extractors populate it with the raw EMR date string and leave normalization to the central extractor.