Remove valueInteger64 handling, keep valueString only for Long results

Scope the change to FHIR R4 for now: a Long result is matched only when
returned as valueString.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01M6fK2KhnNsn28SJfe83Htw

Author: claude

src/extractors/value-type-extractors/integer64-extractor.ts

@@ -4,7 +4,6 @@ import { UndefinedExtractor } from '../extractors/undefined-extractor.js';
 import { StringExtractor } from '../extractors/value-type-extractors/string-extractor.js';
 import { BooleanExtractor } from '../extractors/value-type-extractors/boolean-extractor.js';
 import { IntegerExtractor } from '../extractors/value-type-extractors/integer-extractor.js';
-import { Integer64Extractor } from '../extractors/value-type-extractors/integer64-extractor.js';
 import { DecimalExtractor } from '../extractors/value-type-extractors/decimal-extractor.js';
 import { DateExtractor } from '../extractors/value-type-extractors/date-extractor.js';
 import { DateTimeExtractor } from '../extractors/value-type-extractors/datetime-extractor.js';
@@ -28,7 +27,6 @@ export function buildExtractor(): ResultExtractor {
     .setNextExtractor(new StringExtractor())
     .setNextExtractor(new BooleanExtractor())
     .setNextExtractor(new IntegerExtractor())
-    .setNextExtractor(new Integer64Extractor())
     .setNextExtractor(new DecimalExtractor())
     .setNextExtractor(new DateExtractor())
     .setNextExtractor(new DateTimeExtractor())

src/server/extractor-builder.ts

@@ -1,7 +1,7 @@
 /**
  * Compares an expected CQL Long (parsed to a BigInt by cvl) against the actual value.
- * A Long result must be returned as valueString (FHIR R4 has no integer64 type) or
- * as valueInteger64 (serialized as a JSON string), so the actual is a string either way.
+ * FHIR R4 has no integer64 type, so a Long result is returned as valueString and the
+ * extracted actual is a string.
  */
 function longEquals(expected: bigint, actual: any): boolean {
 	if (typeof actual === 'bigint') {

src/shared/results-utils.ts

@@ -38,20 +38,6 @@ test('integer response check', () => {
 	).toBe(1);
 });
 
-test('integer64 response check', () => {
-	expect(
-		extractor!.extract({
-			resourceType: 'Parameters',
-			parameter: [
-				{
-					name: 'return',
-					valueInteger64: '9223372036854775807',
-				},
-			],
-		})
-	).toBe('9223372036854775807');
-});
-
 test('decimal(0.1) response check', () => {
 	expect(
 		extractor!.extract({