FHIR-57053: compare the distinguishing properties in the report invariants

[patrick-werner]

Resolves FHIR-57053 (Persuasive with Modification).

Changes

dr-comp-type — "change the comparison to system + code + version":

entry.resource.ofType(Composition).type.coding.select(system & '|' & version & '|' & code)
  .intersect(entry.resource.ofType(DiagnosticReport).code.coding.select(system & '|' & version & '|' & code)).exists()

dr-comp-category — removed, together with its * obeys on the Bundle profile ("Category of DR and Composition could be not the same, one is the categorization of the document, the other one about the medical discipline of the DR").

dr-comp-identifier — same comparison approach:

entry.resource.ofType(DiagnosticReport).identifier.exists() implies
  entry.resource.ofType(Composition).identifier.select(system & '|' & value)
    .intersect(entry.resource.ofType(DiagnosticReport).identifier.select(system & '|' & value)).exists()

& is used rather than + so that codings without a version still produce a comparable string instead of dropping out.

Points that needed a call

• The resolution says "system + code + version" for dr-comp-identifier as well; Identifier has neither code nor version, so the analogous properties system and value are compared — as the issue description proposed.
• The implication condition was narrowed to DiagnosticReport.identifier.exists(). With the previous or the invariant failed when only the Composition carried an identifier, which its description never claimed. This was raised in the issue description but not repeated in the resolution.
• With dr-comp-category gone, the comment "DiagnosticReport.category and Composition.category shall be aligned" in ReportCategoryRule would have contradicted the resolution, so it was removed (affects Composition.category and DiagnosticReport.category).
• Both descriptions now name the compared properties instead of saying "SHALL be equal".

All example bundles satisfy both invariants (checked type/code codings and identifiers of Composition and DiagnosticReport in the five generated bundles). SUSHI: 0 errors.