BAH-4336 | Refactor. HL7 Service to extract out mappers for each segment

[mohan-13]

Summary

Refactored HL7 message generation by extracting monolithic HL7Service into specialized segment mappers, improving maintainability and separation of concerns.

Key Changes

• Created dedicated mappers: MessageHeaderMapper, PatientIdentificationMapper, ORCMapper, OBRMapper, ZDSMapper
• Introduced HL7MessageCreator interface to orchestrate mapper usage
• Extended OpenMRSOrderDetails with creator, patient, and base order information
• Enhanced StudyInstanceUIDGenerator to include order creation date for better uniqueness
• Introduced ConceptCodeResolver service for centralized concept code resolution
• Eliminated separate API calls for patient and provider data - now embedded in OpenMRSOrderDetails

Additional Fields Mapped

• MSH: Dynamic sending/receiving facilities via LocationResolver (location-aware routing)
• OBR: Ordering provider now includes structured name (given + family) from order creator
• OBR: Universal Service Identifier now includes:
  • nameOfCodingSystem (coding system for primary identifier)
  • alternateIdentifier (duplicate identifier for compatibility)
  • alternateText (duplicate text for compatibility)
  • nameOfAlternateCodingSystem (coding system for alternate identifier)
• ZDS: Study Instance UID generation includes dateCreated for improved uniqueness
• ORC: Priority properly mapped as "S" (STAT) or "R" (routine) instead of raw urgency value

Fields No Longer Mapped

• OBR: Reason for study (commentToFulfiller)
• OBR: Collector's comment (concept display name)
• OBR: Planned patient transport comment (patient name concatenation)

Architectural Changes

• Concept code resolution now centralized via ConceptCodeResolver service instead of direct PACS concept source lookup
• Ordering provider moved from ORC segment to OBR segment (correct HL7 placement)
• Mapper pattern enables independent testing and easier maintenanc