test: preserve fee item identifiers

scripts/admin-test-env-modules/finance-full-fixtures-contract.test.mjs

@@ -52,6 +52,12 @@ test('Finance PAYABLE fixture creates an isolated ACTIVE supplier through the fo
   assert.match(source, /detail\?\.status === 'ACTIVE' && detail\?\.category === category/)
 })
 
+test('fee detail writes preserve 19-digit fee item IDs as strings', () => {
+  assert.doesNotMatch(source, /feeItemId: Number\(/)
+  assert.match(source, /feeItemId: String\(feeItem\.id\)/)
+  assert.match(source, /feeItemId: String\(feeItems\.PAYABLE\.id\)/)
+})
+
 test('automatic fee fixture completes the reviewed pricing workflow without recalculating', () => {
   assert.match(source, /latest\?\.feeId/)
   assert.doesNotMatch(source, /latest\?\.id/)