[DRAFT] Create a FHIR validator implementation

[thetaurean]

User Story:

As a developer, I need to perform various types of validation on FHIR bundles in numerous contexts so that I can validate data at various stages in the pipeline.

Description/Use Case

Implement a FHIR validator following the design patterns established in #9597.

Risks/Impacts/Considerations

Dev Notes:

See the design document in the repo for some code examples and more relevant information

Acceptance Criteria

• FHIR validator implemented as an extension of abstract validation components
• FHIR validator supports multiple types of validation: at least Instance and IParser based validation (from FHIR HAPI library)

[bishoyayoub]

@thetaurean Please move to ready for grooming or let me know if we should icebox this story.