fix(pii): fail fast on a null mask-batch body; use sleep() in gate test

A 200 response with a null JSON body threw TypeError on the data.masked read,
which the retry classifier treats as transient — burning the full retry budget
on a deterministic shape failure. Null-guard the body so it throws the
non-retryable shape error immediately. Also swap the gate test's inline
setTimeout promise for sleep() to satisfy check:utils, which failed CI.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01A1JYstmLHk9qMGyBDqYRcJ

Author: TheodoreSpeaks

apps/sim/lib/guardrails/mask-client.test.ts

@@ -109,6 +109,16 @@ describe('maskPIIBatchViaHttp', () => {
     expect(mockToken).toHaveBeenCalledTimes(2)
   })
 
+  it('does not retry a null 200 body (deterministic, not a transient TypeError)', async () => {
+    fetchMock.mockResolvedValueOnce(
+      new Response('null', { status: 200, headers: { 'content-type': 'application/json' } })
+    )
+
+    await expect(maskPIIBatchViaHttp(['a'], [])).rejects.toThrow(/unexpected result/)
+    expect(fetchMock).toHaveBeenCalledTimes(1)
+    expect(mockSleep).not.toHaveBeenCalled()
+  })
+
   it('does not retry a shape mismatch (deterministic server bug)', async () => {
     fetchMock.mockResolvedValueOnce(
       new Response(JSON.stringify({ nope: true }), {

apps/sim/lib/guardrails/mask-client.ts

@@ -166,8 +166,8 @@ async function postChunkOnce(
     )
   }
 
-  const data = (await response.json()) as GuardrailsMaskBatchResult
-  if (!Array.isArray(data.masked)) {
+  const data = (await response.json()) as GuardrailsMaskBatchResult | null
+  if (!data || !Array.isArray(data.masked)) {
     throw new Error('PII mask-batch returned an unexpected result')
   }
   return data.masked

apps/sim/lib/logs/execution/pii-large-values.test.ts

@@ -1,6 +1,7 @@
 /**
  * @vitest-environment node
  */
+import { sleep } from '@sim/utils/helpers'
 import { beforeEach, describe, expect, it, vi } from 'vitest'
 
 const { mockMaterializeRef, mockStoreLargeValue, mockCompact, mockMaskBatch } = vi.hoisted(() => ({
@@ -244,7 +245,7 @@ describe('redactLargeValueRefs', () => {
       if (ref.size > 16 * 1024 * 1024) {
         inFlight++
         maxInFlight = Math.max(maxInFlight, inFlight)
-        await new Promise((resolve) => setTimeout(resolve, 1))
+        await sleep(1)
         inFlight--
       }
       return chunkData.get(ref.id)