Build a patient ADT message and send it over URL or TCP/IP

Build the HL7 ADT message for a patient event and deliver it. Delivers over HTTP to ``integration_configs.url`` when present, otherwise over TCP/IP to the ``host``/``port`` resolved from ``config_meta`` (falling back to ``integration_details``). Fire-and-forget (no ACK/response body is awaited beyond an HTTP status check). Returns ``{sent, ..., version, segment_count, hl7_message}`` on success. Raises 422 when the payload is invalid, and 502 when the receiver cannot be reached.