test(integration): address Gemini review — harden waitFor/awaitJob

Apply the three medium-priority suggestions from the gemini-code-assist
review on PR #1233:

- waitFor: wrap produce/until in try/catch, swallowing a transient failure
  (e.g. a momentary non-200 under CI contention) and retrying; re-throw only
  on the final attempt so a persistent failure still surfaces. Supersedes the
  earlier "keep it strict" choice — the retry-then-final-rethrow semantic is
  the better default for a reusable contention-riding poll helper.
- awaitJob: optional-chain response.body?.[0]?.status to avoid a TypeError on
  a null/empty body.
- row_count assertion: optional-chain r.body?.[0]?.row_count so a malformed
  body yields a clean assertion diff rather than a property-access throw.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: heskew

integrationTests/apiTests/northwind.test.mjs

@@ -8760,7 +8760,7 @@ suite('Northwind operations', { skip: skipSuite }, (ctx) => {
 						.expect(200),
 				{ until: (res) => res.body?.[0]?.row_count === 30, timeoutSeconds: isBunRuntime ? 60 : 15 }
 			);
-			assert.equal(r.body[0].row_count, 30, r.text);
+			assert.equal(r.body?.[0]?.row_count, 30, r.text);
 		});
 
 		test.skip('Import CSV from S3 to table w/ full attr perms - update', async () => {

integrationTests/apiTests/utils/operations.mjs

@@ -28,7 +28,7 @@ export async function awaitJob(client, jobId, timeoutSeconds = 15) {
 	let elapsed = 0;
 	do {
 		response = await client.req().send({ operation: 'get_job', id: jobId }).expect(200);
-		const status = response.body[0]?.status;
+		const status = response.body?.[0]?.status;
 		// Stop only on a terminal status. A freshly-started job is briefly
 		// CREATED (queued, before the worker flips it to IN_PROGRESS) and a
 		// just-created job record can momentarily come back empty; returning on
@@ -87,6 +87,10 @@ export async function awaitJobCompleted(client, jobId, options = {}) {
  * an asynchronous side effect — the source of the fixed-delay races in #1222.
  *
  * @template T
+ * A transient failure from `produce`/`until` (e.g. a momentary non-200 under CI
+ * contention) is swallowed and retried; the error is re-thrown only if it
+ * happens on the final attempt, so a persistent failure still surfaces.
+ *
  * @param {() => Promise<T> | T} produce  Produces the current value (e.g. runs a query).
  * @param {{ until: (value: T) => boolean, timeoutSeconds?: number, intervalMs?: number }} options
  * @returns {Promise<T>} the last produced value (satisfying `until`, or the final attempt on timeout)
@@ -95,8 +99,12 @@ export async function waitFor(produce, { until, timeoutSeconds = 30, intervalMs
 	const attempts = Math.max(1, Math.ceil((timeoutSeconds * 1000) / intervalMs));
 	let value;
 	for (let attempt = 0; attempt < attempts; attempt++) {
-		value = await produce();
-		if (until(value)) return value;
+		try {
+			value = await produce();
+			if (until(value)) return value;
+		} catch (error) {
+			if (attempt === attempts - 1) throw error;
+		}
 		if (attempt < attempts - 1) await setTimeout(intervalMs);
 	}
 	return value;