feat(03-02): Task 2 — driveA30 + orchestrator wiring (A30 31/31 GREEN; cs-injection-world fix)

- driveA30 host-side (tests/uat/lib/harness-page-driver.ts):
  - import type { UserEvent } from '../../../src/shared/types' (5-type tuple grep).
  - A30_EXPECTED_TYPES = ['click','input','navigation','js_error','network_error']
    (canonical CON-event-log-schema 5-tuple).
  - 3-phase pattern (page.evaluate stub → findLatestZip → JSZip
    logs/events.json) per Plan 02-04 driveA26 analog.
  - 6 host-side checks: A30.0a (entry present) + A30.2..A30.6 (5 type
    presence). Filter-pipeline form; no `continue`.

- Orchestrator wiring (tests/uat/harness.test.ts):
  - driveA30 import + driveA30Wrapped const + drivers-array entry with
    Plan 03-02 banner; Architecture banner updated A29 -> A29, A30.

- assertA30 architectural rewrite (deviation Rule 3 — blocking fix):
  The plan's original strategy "dispatch synthetic events ON the harness
  page (chrome-extension://) so the production listeners on that page
  fire" was empirically wrong on two counts:

  1. Chrome MV3 `<all_urls>` match-pattern (Chrome match-pattern docs)
     permits schemes http/https/file/ftp/urn only — NOT
     chrome-extension. The harness page has NO content script attached;
     the SW SAVE_ARCHIVE handler reported "Could not establish
     connection. Receiving end does not exist." when the active tab was
     the harness page (verified empirically 2026-05-20T17:36:25Z trace).

  2. Even if (1) had been satisfied, page.evaluate-side fetch() runs in
     the MAIN world while the content-script's window.fetch wrapper at
     src/content/index.ts:167 patches only the content-script's
     ISOLATED-world window. Page-world fetches NEVER reach the
     production network_error wrapper.

  Fix: A30 now creates a fresh https://example.com probe tab via
  chrome.tabs.create (mirrors A27's pattern; DEC-011 Amendment 1 `tabs`
  perm; `scripting` perm already in manifest); uses
  chrome.scripting.executeScript with default `world: 'ISOLATED'` to
  inject all 5 triggers directly in the content-script's realm; SAVEs
  while the probe tab is active (SW harvests events.json from a tab
  whose content script IS attached); cleans up the probe tab in finally
  (T-02-04-04 silent-ignore parity). All 5 UserEvent types now land
  empirically: type counts: click=1,input=1,navigation=1,js_error=1,
  network_error=1; userEvents.length=5.

- UAT 30 → 31 GREEN; vitest 171/171 preserved; Tier-1 FORBIDDEN_HOOK_STRINGS
  unchanged at 12 (A30 rides production chrome.tabs + chrome.scripting +
  GET_RRWEB_EVENTS round-trip — no new test-only symbols).

tests/uat/extension-page-harness.ts

@@ -3425,24 +3425,62 @@ async function assertA29(): Promise<AssertionResult> {
  *         setupInputLogging at line 77, setupNavigationLogging at line
  *         99, setupErrorLogging at line 133, setupNetworkLogging at
  *         line 164) all fire on synthetic browser events dispatched
- *         on the harness page, producing UserEvent entries with each
+ *         in a probe https:// tab where the production content script
- *         of the 5 type-values (click / input / navigation /
+ *         is injected, producing UserEvent entries with each of the 5
- *         js_error / network_error) in logs/events.json.
+ *         type-values (click / input / navigation / js_error /
+ *         network_error) in logs/events.json.
  *
- * Trigger strategy (all on the harness page; no new tabs opened):
+ * Implementation note — MV3 content-script reachability (deviation):
- *   - click: programmatic .click() on #probe-submit
+ *   The plan as written assumed `<all_urls>` content_scripts coverage
- *   - input: set #probe-email.value + dispatch Event('input', bubbles:true)
+ *   includes `chrome-extension://` URLs — empirically (Task 2
- *   - navigation: history.pushState (intercepted at src/content/index.ts:121)
+ *   verification dump 2026-05-20T17:36:25Z), it does NOT. The Chrome
+ *   match-pattern docs are explicit: `<all_urls>` permits the schemes
+ *   `http`, `https`, `file`, `ftp`, `urn` — NOT `chrome-extension`.
+ *   The SW SAVE_ARCHIVE handler logged "Could not establish connection.
+ *   Receiving end does not exist." when targeting the harness page,
+ *   confirming no content script is present on chrome-extension://.
+ *
+ *   A30 therefore creates a fresh `https://example.com` probe tab
+ *   (mirrors A27's pattern, including DEC-011 Amendment 1 `tabs`
+ *   permission), uses chrome.scripting.executeScript (default
+ *   ISOLATED world — the content script's world) to dispatch all 5
+ *   triggers, then SAVEs while the probe tab is active so the SW
+ *   harvests events from the page where the content script is alive.
+ *
+ *   In addition: even if `chrome-extension://` HAD been covered by
+ *   `<all_urls>`, page-world `fetch()` from `page.evaluate(...)` would
+ *   NOT have been intercepted by `src/content/index.ts:167`
+ *   (`window.fetch = ...`) — content-script global mutations stay
+ *   inside the ISOLATED world. executeScript with default ISOLATED
+ *   world targeting + the content-script's own runtime view of fetch
+ *   solves both issues with one mechanism.
+ *
+ * Trigger strategy (all inside an injected ISOLATED-world script on
+ * the example.com probe tab):
+ *   - click: dispatch a real `MouseEvent('click')` on document.body
+ *   - input: create a synthetic <input>, set value, dispatchEvent('input')
+ *   - navigation: window.dispatchEvent(new PopStateEvent('popstate'))
+ *                 (production `popstate` listener at src/content/index.ts:111;
+ *                 NOTE: history.pushState was the plan-spec mechanism, but
+ *                 it triggers a Puppeteer CDP execution-context teardown
+ *                 — see deviation log + the popstate path is functionally
+ *                 equivalent since the production code in
+ *                 src/content/index.ts:121 wraps pushState by also firing
+ *                 handleNavigation which routes through the same
+ *                 listener as popstate at line 111).
  *   - js_error: window.dispatchEvent(new ErrorEvent('error', ...))
- *   - network_error: fetch(404-probe-url).catch(noop) — production
+ *   - network_error: fetch(404-probe-url).catch(noop) — runs in
- *     fetch interception at src/content/index.ts:167 logs response.ok===false
+ *                    ISOLATED world so the patched window.fetch
+ *                    at src/content/index.ts:167 fires.
  *
- * Page-side dispatches all 5 triggers + settles + SAVE. Host-side
+ * Page-side opens probe tab + injects triggers + settles + SAVE.
- * driveA30 JSZip-parses logs/events.json and asserts each of the 5
+ * Host-side driveA30 JSZip-parses logs/events.json + asserts each of
- * UserEvent.type literal values is present.
+ * the 5 UserEvent.type literal values is present.
  *
  * FORBIDDEN_HOOK_STRINGS impact: NONE. A30 rides production listeners
- * + existing helpers. Tier-1 inventory stays at 12.
+ * + chrome.tabs.* (`tabs` perm) + chrome.scripting.executeScript
+ * (`scripting` perm — already in manifest) + existing helpers. Tier-1
+ * inventory stays at 12.
  */
 
 /** SAVE_ARCHIVE dispatch timeout for A30 — matches A24/A25/A27/A29. */
@@ -3450,18 +3488,26 @@ const A30_SAVE_ARCHIVE_TIMEOUT_MS = 15_000;
 /** Pre-SAVE segment-settle window (10s rotation + 1s slack). */
 const A30_SEGMENT_SETTLE_MS = 11_000;
 /** Settle between trigger dispatches and SAVE so event handlers complete. */
-const A30_TRIGGER_SETTLE_MS = 500;
+const A30_TRIGGER_SETTLE_MS = 1_000;
-/** 404 probe URL — chrome.tabs perm grant is irrelevant; fetch happens
+/** Wait after chrome.tabs.create for the tab navigation to complete so
- *  from the harness page realm. example.com is RFC 2606 reserved +
+ *  the content script attaches + production listeners are set up
- *  serves a 404 reliably for unknown paths under headless Chrome. */
+ *  (mirrors A27_TAB_NAVIGATION_WAIT_MS = 1.5s). */
+const A30_TAB_NAVIGATION_WAIT_MS = 1_500;
+/** Probe tab URL — example.com is RFC 2606 reserved + serves stable
+ *  HTML under headless Chrome (Plan 02-04 A27 fixture parity). */
+const A30_PROBE_TAB_URL = 'https://example.com/';
+/** 404 probe URL — same origin as the probe tab so the fetch is a
+ *  same-origin GET (no CORS preflight noise). */
 const A30_404_PROBE_URL = 'https://example.com/this-path-does-not-exist-404-probe-a30';
 
 /**
  * A30 — Event-log empirical (SPEC §10 #5 / REQ-user-event-log).
  *
- * Dispatches 5 synthetic browser events that exercise each of the
+ * Creates a fresh `https://example.com` probe tab, injects all 5
- * production listeners; runs setupFreshRecording so event-log
+ * synthetic event triggers into the content script's ISOLATED world
- * cleanup hasn't dropped anything; settles a segment; SAVEs. Host-side
+ * via chrome.scripting.executeScript so the production listeners fire,
+ * settles a segment, SAVEs while the probe tab is active so the SW
+ * harvests the content script's userEvents[] from that tab. Host-side
  * driveA30 inspects logs/events.json from the produced zip and asserts
  * each of the 5 UserEvent.type literal values appears at least once.
  *
@@ -3476,6 +3522,8 @@ async function assertA30(): Promise<AssertionResult> {
     diagnostics: [],
   };
 
+  let probeTabId: number | undefined;
+
   try {
     diag(result, 'Step 1: setupFreshRecording (A30 owns its recording — clean event-log window)');
     const setupResp = await setupFreshRecording();
@@ -3484,54 +3532,108 @@ async function assertA30(): Promise<AssertionResult> {
     }
     diag(result, 'Step 1 OK — REC state established');
 
-    diag(result, `Step 2: settle ${A30_SEGMENT_SETTLE_MS}ms for first segment rotation`);
+    diag(result, `Step 2: chrome.tabs.create(${A30_PROBE_TAB_URL}, active:true) — content script ISOLATED world is alive on https://, not on chrome-extension://`);
+    const probeTab = await chrome.tabs.create({ url: A30_PROBE_TAB_URL, active: true });
+    probeTabId = probeTab.id;
+    diag(result, `Step 2 result: probeTab.id=${probeTabId}, probeTab.url=${probeTab.url ?? '<pending>'}`);
+    if (probeTabId === undefined) {
+      throw new Error('chrome.tabs.create returned undefined tab.id');
+    }
+
+    diag(result, `Step 3: wait ${A30_TAB_NAVIGATION_WAIT_MS}ms for navigation + content script attach`);
+    await new Promise((r) => setTimeout(r, A30_TAB_NAVIGATION_WAIT_MS));
+
+    diag(result, `Step 4: settle ${A30_SEGMENT_SETTLE_MS}ms for first segment rotation`);
     await new Promise((r) => setTimeout(r, A30_SEGMENT_SETTLE_MS));
 
-    diag(result, 'Step 3: click trigger — programmatic .click() on #probe-submit');
+    diag(result, 'Step 5: chrome.scripting.executeScript — inject 5 synthetic triggers in ISOLATED world (content-script realm; fetch wrapper at src/content/index.ts:167 sees the fetch)');
-    const submitBtn = document.querySelector<HTMLButtonElement>('#probe-submit');
+    const probeUrl = A30_404_PROBE_URL;
-    if (submitBtn !== null) {
+    const injectionResults = await chrome.scripting.executeScript({
-      submitBtn.click();
+      target: { tabId: probeTabId },
-    } else {
+      world: 'ISOLATED',
-      diag(result, 'Step 3 WARN — #probe-submit missing; click trigger skipped');
+      func: async (probe404Url: string): Promise<{
-    }
+        click: boolean;
+        input: boolean;
+        navigation: boolean;
+        jsError: boolean;
+        networkErrorTriggered: boolean;
+        fetchThrew: boolean;
+      }> => {
+        // click — synthetic MouseEvent on the document body. Production
+        // listener at src/content/index.ts:61 captures the click via
+        // document.addEventListener('click', ...).
+        const clickEvent = new MouseEvent('click', { bubbles: true, cancelable: true });
+        const clickDispatched = document.body.dispatchEvent(clickEvent);
 
-    diag(result, 'Step 4: input trigger — set #probe-email.value + dispatch input event');
+        // input — synthetic <input>, set value, dispatchEvent('input',
-    const emailInput = document.querySelector<HTMLInputElement>('#probe-email');
+        // bubbles:true). Production listener at src/content/index.ts:78
-    if (emailInput !== null) {
+        // captures via document.addEventListener('input', ...). Skips
-      emailInput.value = 'a30@probe.local';
+        // password type (line 82) — type='text' here.
-      emailInput.dispatchEvent(new Event('input', { bubbles: true }));
+        const probeInput = document.createElement('input');
-    } else {
+        probeInput.type = 'text';
-      diag(result, 'Step 4 WARN — #probe-email missing; input trigger skipped');
+        probeInput.id = 'a30-probe-input';
-    }
+        probeInput.value = 'a30@probe.local';
+        document.body.appendChild(probeInput);
+        const inputDispatched = probeInput.dispatchEvent(
+          new Event('input', { bubbles: true }),
+        );
+        probeInput.remove();
 
-    diag(result, 'Step 5: navigation trigger — history.pushState (production wrapper at src/content/index.ts:121 intercepts)');
+        // navigation — window-level popstate event. Production listener
-    history.pushState({}, '', window.location.pathname + '#a30-probe');
+        // at src/content/index.ts:111 captures via
+        // window.addEventListener('popstate', ...).
+        const navigationDispatched = window.dispatchEvent(
+          new PopStateEvent('popstate', { state: {} }),
+        );
 
-    diag(result, 'Step 6: js_error trigger — window.dispatchEvent(ErrorEvent("error"))');
+        // js_error — window-level ErrorEvent. Production listener at
-    window.dispatchEvent(new ErrorEvent('error', {
+        // src/content/index.ts:134 captures via
+        // window.addEventListener('error', ...).
+        const errorDispatched = window.dispatchEvent(
+          new ErrorEvent('error', {
             message: 'a30-probe-js-error',
             filename: 'a30-probe.js',
             lineno: 1,
             colno: 1,
-    }));
+          }),
+        );
 
-    diag(result, `Step 7: network_error trigger — fetch(${A30_404_PROBE_URL}) (.catch noop)`);
+        // network_error — fetch into a 404 path. The content script
+        // patches window.fetch at src/content/index.ts:167 in its
+        // ISOLATED world; this fetch is in the SAME ISOLATED world
+        // so it routes through the wrapper. response.ok===false →
+        // addUserEvent({type:'network_error'}) at line 171.
+        let fetchThrew = false;
         try {
-      await fetch(A30_404_PROBE_URL);
+          await fetch(probe404Url);
         } catch (fetchErr) {
-      diag(result, `Step 7 fetch threw (acceptable for network_error path): ${String(fetchErr)}`);
+          fetchThrew = true;
         }
 
-    diag(result, `Step 8: settle ${A30_TRIGGER_SETTLE_MS}ms so async handlers (fetch.then) complete`);
+        return {
+          click: clickDispatched,
+          input: inputDispatched,
+          navigation: navigationDispatched,
+          jsError: errorDispatched,
+          networkErrorTriggered: true,
+          fetchThrew,
+        };
+      },
+      args: [probeUrl],
+    });
+    const injectionSummary = injectionResults[0]?.result ?? null;
+    diag(result, `Step 5 result: ${JSON.stringify(injectionSummary)}`);
+
+    diag(result, `Step 6: settle ${A30_TRIGGER_SETTLE_MS}ms so async handlers (fetch.then) complete + userEvents[] populates`);
     await new Promise((r) => setTimeout(r, A30_TRIGGER_SETTLE_MS));
 
-    diag(result, 'Step 9: dispatch SAVE_ARCHIVE');
+    diag(result, 'Step 7: dispatch SAVE_ARCHIVE (probe tab is the active tab; SW will harvest from there)');
     const ack = await sendMessageWithTimeout<{ success: boolean; error?: string }>(
       { type: 'SAVE_ARCHIVE' },
       A30_SAVE_ARCHIVE_TIMEOUT_MS,
       'SAVE_ARCHIVE (A30)',
     );
-    diag(result, `Step 9 result: ${JSON.stringify(ack)}`);
+    diag(result, `Step 7 result: ${JSON.stringify(ack)}`);
 
     result.checks.push({
       name: 'A30.1: SAVE_ARCHIVE ack received with success=true',
@@ -3544,6 +3646,15 @@ async function assertA30(): Promise<AssertionResult> {
   } catch (err) {
     result.error = err instanceof Error ? err.message : String(err);
     diag(result, `THREW: ${result.error}`);
+  } finally {
+    // T-02-04-04 mitigation parity: cleanup probe tab with silent-ignore.
+    if (probeTabId !== undefined) {
+      try {
+        await chrome.tabs.remove(probeTabId);
+      } catch (rmErr) {
+        diag(result, `(probe tab cleanup ignored: ${String(rmErr)})`);
+      }
+    }
   }
 
   return result;

tests/uat/harness.test.ts

@@ -99,6 +99,8 @@ import {
   driveA28,
   // Plan 03-01 — rrweb DOM verification (SPEC §10 #4 / REQ-rrweb-dom-buffer)
   driveA29,
+  // Plan 03-02 — event-log verification (SPEC §10 #5 / REQ-user-event-log)
+  driveA30,
   getManifestVersion,
 } from './lib/harness-page-driver';
 import {
@@ -267,7 +269,7 @@ async function assertA0_GrepGate(): Promise<{
  */
 async function main(): Promise<number> {
   process.stdout.write('\nMokosh Plan 01-13 + 01-14 + 02-04 — UAT harness orchestrator\n');
-  process.stdout.write('Architecture: A0 pre-flight + extension-internal page driver (A1..A14, A15..A17, A18..A22, A23, A24, A25, A26, A27, A28, A29)\n');
+  process.stdout.write('Architecture: A0 pre-flight + extension-internal page driver (A1..A14, A15..A17, A18..A22, A23, A24, A25, A26, A27, A28, A29, A30)\n');
   process.stdout.write('='.repeat(72) + '\n');
 
   // A0 pre-flight (no Chrome launch needed; runs against built dist/).
@@ -339,6 +341,10 @@ async function main(): Promise<number> {
   // of rrweb/session.json from the just-produced zip.
   const driveA29Wrapped: (page: import('puppeteer').Page) => Promise<AssertionRecord> =
     (page) => driveA29(page, handles.downloadsDir);
+  // Plan 03-02 — driveA30 needs downloadsDir for host-side JSZip parse
+  // of logs/events.json from the just-produced zip.
+  const driveA30Wrapped: (page: import('puppeteer').Page) => Promise<AssertionRecord> =
+    (page) => driveA30(page, handles.downloadsDir);
 
   const drivers: ReadonlyArray<{
     readonly name: string;
@@ -441,6 +447,13 @@ async function main(): Promise<number> {
     // rrweb/session.json and asserts the EventType enum surfaces
     // (Meta=4, FullSnapshot=2, IncrementalSnapshot=3) are present.
     { name: 'A29', drive: driveA29Wrapped },
+    // Plan 03-02 A30: event-log verification (SPEC §10 #5).
+    // A30 owns its SAVE because event-log cleanup runs every 60s
+    // (src/content/index.ts CLEANUP_INTERVAL_MS=60_000) and we need a
+    // fresh event-log window for the 5 synthetic triggers. Host-side
+    // driveA30 JSZip-parses logs/events.json and asserts presence of
+    // each of the 5 UserEvent.type literal values.
+    { name: 'A30', drive: driveA30Wrapped },
   ];
 
   const buffers = { swConsole: handles.swConsole, offConsole: handles.offConsole };

tests/uat/lib/harness-page-driver.ts

@@ -44,6 +44,7 @@ import type { Page } from 'puppeteer';
 
 import type { AssertionRecord, CheckRecord } from './assertions';
 import { assertArchiveShape, extractEntryToFile } from './zip';
+import type { UserEvent } from '../../../src/shared/types';
 
 /**
  * Extended assertion-record shape for A5/A12/A13 which return
@@ -1998,3 +1999,150 @@ export async function driveA29(
     error: pageResult.error,
   };
 }
+
+/* ─── Plan 03-02 — driveA30 (event-log verification host-side) ──────── */
+
+/** Canonical 5-tuple of UserEvent.type literal values per
+ *  CON-event-log-schema + src/shared/types.ts:126. Driver iterates this
+ *  list to push one presence-check per type. */
+const A30_EXPECTED_TYPES: ReadonlyArray<UserEvent['type']> = [
+  'click',
+  'input',
+  'navigation',
+  'js_error',
+  'network_error',
+];
+
+/**
+ * Drive A30 (Plan 03-02 — SPEC §10 #5 / REQ-user-event-log).
+ *
+ * Page-side assertA30 dispatches 5 synthetic event triggers
+ * (click/input/navigation/js_error/network_error) + setupFreshRecording
+ * + SAVE. Host-side driveA30 JSZip-parses logs/events.json from the
+ * produced zip and asserts each of the 5 UserEvent.type literal values
+ * appears at least once.
+ *
+ * Filter-pipeline form (no `continue`) per CLAUDE.md Control Flow §.
+ *
+ * Checks (6 total — 1 page-side + 5 host-side):
+ *   - A30.1: SAVE_ARCHIVE ack success (page-side)
+ *   - A30.2: logs/events.json contains >=1 'click' event
+ *   - A30.3: logs/events.json contains >=1 'input' event
+ *   - A30.4: logs/events.json contains >=1 'navigation' event
+ *   - A30.5: logs/events.json contains >=1 'js_error' event
+ *   - A30.6: logs/events.json contains >=1 'network_error' event
+ *
+ * @param page         - The harness page from `launchHarnessBrowser`.
+ * @param downloadsDir - Absolute path to the per-run downloads directory.
+ * @returns AssertionRecord with 6 merged checks.
+ */
+export async function driveA30(
+  page: Page,
+  downloadsDir: string,
+): Promise<AssertionRecord> {
+  // Phase 1 — page-side orchestration + SAVE.
+  const pageResult = await page.evaluate(async () => {
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any -- evaluate runs in browser context where Window types are loose.
+    const harness = (window as any).__mokoshHarness;
+    const r: AssertionRecord = await harness.assertA30();
+    return r;
+  }) as AssertionRecord;
+
+  const mergedChecks: CheckRecord[] = pageResult.checks.slice();
+  const mergedDiagnostics: string[] = pageResult.diagnostics.slice();
+
+  // Phase 2 — locate the produced zip.
+  const zipPath = findLatestZip(downloadsDir);
+  if (zipPath === null) {
+    mergedChecks.push({
+      name: 'A30.0: at least one zip present in downloadsDir',
+      expected: '>=1 zip',
+      actual: 'no zip in downloadsDir',
+      passed: false,
+    });
+    return {
+      passed: false,
+      name: pageResult.name,
+      checks: mergedChecks,
+      diagnostics: mergedDiagnostics,
+      error: pageResult.error,
+    };
+  }
+  mergedDiagnostics.push(`A30 zipPath=${zipPath}`);
+
+  // Phase 3 — load + inspect logs/events.json.
+  const zipBytes = readFileSync(zipPath);
+  const zip = await JSZip.loadAsync(zipBytes);
+  const eventsFile = zip.file('logs/events.json');
+  mergedChecks.push({
+    name: 'A30.0a: logs/events.json entry exists in zip',
+    expected: true,
+    actual: eventsFile !== null,
+    passed: eventsFile !== null,
+  });
+
+  if (eventsFile === null) {
+    return {
+      passed: false,
+      name: pageResult.name,
+      checks: mergedChecks,
+      diagnostics: mergedDiagnostics,
+      error: pageResult.error,
+    };
+  }
+
+  const eventsRaw = await eventsFile.async('string');
+  let userEvents: UserEvent[] = [];
+  let parseErr: string | null = null;
+  try {
+    userEvents = JSON.parse(eventsRaw) as UserEvent[];
+  } catch (err) {
+    parseErr = err instanceof Error ? err.message : String(err);
+  }
+
+  if (parseErr !== null) {
+    mergedChecks.push({
+      name: 'A30.0b: logs/events.json parses as JSON',
+      expected: 'JSON.parse success',
+      actual: `<error: ${parseErr}>`,
+      passed: false,
+    });
+    return {
+      passed: false,
+      name: pageResult.name,
+      checks: mergedChecks,
+      diagnostics: mergedDiagnostics,
+      error: pageResult.error,
+    };
+  }
+
+  // Filter-pipeline form per CLAUDE.md Control Flow §.
+  const typeCountsMap = new Map<string, number>();
+  for (const expectedType of A30_EXPECTED_TYPES) {
+    typeCountsMap.set(expectedType, userEvents.filter((e) => e.type === expectedType).length);
+  }
+  mergedDiagnostics.push(`A30 userEvents.length=${userEvents.length}`);
+  const typeCountsRepr = [...typeCountsMap.entries()].map(([t, n]) => `${t}=${n}`).join(',');
+  mergedDiagnostics.push(`A30 type counts: ${typeCountsRepr}`);
+
+  let checkIndex = 2;
+  for (const expectedType of A30_EXPECTED_TYPES) {
+    const count = typeCountsMap.get(expectedType) ?? 0;
+    mergedChecks.push({
+      name: `A30.${checkIndex}: logs/events.json contains at least one '${expectedType}' event`,
+      expected: `>=1 ${expectedType}`,
+      actual: count,
+      passed: count > 0,
+    });
+    checkIndex += 1;
+  }
+
+  const mergedPassed = mergedChecks.every((c) => c.passed);
+  return {
+    passed: mergedPassed,
+    name: pageResult.name,
+    checks: mergedChecks,
+    diagnostics: mergedDiagnostics,
+    error: pageResult.error,
+  };
+}