Implement IHE PMIR (Patient Master Identity Registry) Mobile Patient Identity Feed to publish patient identity create/update/merge events using FHIR

Steps

1. Confirm PMIR is the right profile: it governs a Patient Identity Supplier pushing FHIR Patient resource creates/updates/merges to Consumers, distinct from PIXm (cross-reference lookup) and PDQm (demographic query), which are pull/query-based.
2. Implement the Mobile Patient Identity Feed [ITI-93] transaction so that when the source system detects a patient master identity change per domain policy, it sends a FHIR Bundle of new/updated Patient resources to the Consumer.
3. Handle the full identity lifecycle the profile addresses — create, update, merge, and deprecate — not just simple create/update.
4. For merge events, ensure the Bundle correctly expresses the link between the surviving and deprecated Patient resources so downstream consumers can reconcile records that were mistakenly duplicated.
5. Implement Subscribe to Patient Updates [ITI-94] if consumers need to register subscription criteria rather than receive a direct unconditional push.
6. Test end-to-end against real duplicate-patient scenarios, since correctly propagating merges to every downstream data custodian is PMIR's core patient-safety value.