FHIR Transformer integration

The Compose stack runs the external healthtag/fhir-transformer image and mounts workingdir/ plus healthtag/. The full transformation implementation is not present in this repository, so mapping behavior must be verified against the exact image version and its source release.

Integration checklist

1. Pin a tested transformer image digest.
2. Configure the hospital/HosXP database connection using installation-specific credentials.
3. Set FHIR_SERVER_URL to the internal HAPI endpoint and verify /metadata from the transformer container.
4. Review the current healthtag/config.json and transformer configuration without committing real credentials.
5. Map and test at least Patient identifiers, encounters, diagnoses, medications, allergies, and local codes required by the deployment.
6. Run with synthetic data first and inspect generated resources for FHIR conformance and the https://healthtag.io Patient identifier.
7. Define retry, duplicate/idempotency, reconciliation, and failure-alert procedures for the selected transformer release.

FILE_UPLOADER_SERVER_URL references a service that is disabled in the current Compose file. Treat document/file behavior as optional and unsupported until that service is intentionally enabled and reviewed.

See FHIR Transformer configuration for the environment-file inventory.