Historia clinica: firma digital + versioned consent + minors' consent banding (CCyC art.26)

Electronic HC entries must be signed with firma digital per Ley 26.529 art.13 (burden-of-proof distinction from firma electronica, Ley 25.506). Consent must be a first-class VERSIONED record, not a boolean. Minors' consent capacity is age-banded per CCyC art.26 (13-16 presumed capable for non-invasive treatment, 16+ treated as adult) and must gate which consent/authoring actions are available. None of this exists yet; v1 (antecedentes lifecycle) does not require it, but any authoring/clinical-note surface built on top of pacientes will. Filed to make the gap visible before that surface is built, not to block v1.