Immunization dates never render: ViewDefinition uses choice-shorthand path `occurrenceDateTime`

Update the Immunization column in Binary-Immunization.json, changing its path from occurrenceDateTime to occurrence. Review ImmunizationItemRenderer and ImmunizationItemConfig for the existing date flow, then verify that Immunization resources display the “Given {date}” subtitle on Android and desktop.

Summary. The immunization section's "Given {date}" subtitle never shows,
against any server. The rendering side is fully wired —
ImmunizationItemRenderer renders the subtitle, ImmunizationItemConfig
ships showDate: true, and the generated state has the occurrenceDate
field — but the column silently never populates.

Cause. Binary-Immunization.json declares the column as:

{
  "name": "occurrenceDate",
  "path": "occurrenceDateTime",
  "type": "http://hl7.org/fhir/StructureDefinition/dateTime"
}

occurrenceDateTime is the FHIR choice-shorthand element name, not a valid
FHIRPath step: Immunization.occurrence[x] is addressed in FHIRPath by its
base name (occurrence, optionally occurrence.ofType(dateTime)), never by
the type-suffixed form. kotlin-fhirpath accordingly resolves only the bare
property ("occurrence" -> this.occurrence in the generated Immunization
accessor), so the shorthand path evaluates to empty — no error, the subtitle
just silently stays absent, which reads as "the data has no date."

Fix (verified). One word in Binary-Immunization.json:

-          "path": "occurrenceDateTime",
+          "path": "occurrence",

kotlin-fhirpath's sealed-interface glue unwraps Immunization.Occurrence.DateTime
to its FhirDateTime value, which lands in the typed occurrenceDate column
as intended. Verified end-to-end on Android and desktop against a live HAPI
server with real Immunization resources (47 of them, mixed date/dateTime
precision) — all dates render.

occurrence.ofType(dateTime) would be the spec-strict form if the engine's
ofType() supports it; the bare path has the advantage of also surviving an
occurrenceString resource, and matches the style already used elsewhere in
the app's views (e.g. the medication view navigates the bare medication
choice).

Happy to send the one-line PR.