feat(test-app): add a Bluesky-depth heavy feed screen

examples/test-app/README.md

@@ -19,6 +19,7 @@ It is intentionally small, but each surface is dense with durable accessibility
 - `Automation lab`: long-press, alert-result, app-event, app-state, appearance, orientation, permission-recovery, log canaries, a flattened (`accessible={true}`) text input, and an Apple Pay sheet hosted in `com.apple.PassbookUIService`
 - `WebView accessibility`: a deterministic semantic fixture plus live websites with varied HTML for native accessibility snapshot verification
 - `Perf lab`: seeded JavaScript render problems for `react-devtools profile`, one per scenario (see [Perf lab](#perf-lab))
+- `Heavy feed`: a Bluesky-shaped home feed whose accessibility tree is deeper than 65 levels (see [Heavy feed](#heavy-feed))
 
 Navigation uses Expo Router native bottom tabs, so the tab bar itself is also part of the test surface.
 
@@ -261,6 +262,23 @@ agent-device react-devtools profile stop
 
 `src/screens/PerfLabScreen.tsx` imports only React and React Native, so it can be copied into a bare React Native app to check the profiler on other React Native versions.
 
+## Heavy feed
+
+**Settings → Open heavy feed** (`open-heavy-feed`) opens a JavaScript-only reproduction of a heavy
+React Native home feed, shaped after Bluesky 1.136. Thirty nested containers stand in for its
+navigation and provider layers. Below them a virtualized list renders posts with avatar, text,
+image, link, quote, and quote-with-media embeds. Every level opts out of view flattening, so the
+native accessibility tree is deeper than 65 levels and holds about 300 raw nodes.
+
+On this screen the XCTest tree capture fails with `kAXErrorIllegalArgument` and recovers through
+private AX, while the simulator accessibility bridge still answers. Use it to reproduce deep-tree
+capture, recovery, and gesture-routing behavior without a third-party app. `wrappers` (default 30)
+and `posts` (default 60) route parameters change the shape.
+
+The stable ids are `heavy-feed-title`, `heavy-feed-liked-count`, `heavy-feed-last-action`, and per
+post `heavy-post-<n>`, `heavy-post-<n>-like`, `-reply`, `-repost`, and `-more`. A like press updates
+`Liked posts: <count>`, and a long press on a post sets `Last action: held post <n>`.
+
 ## Local Agent Device suites
 
 The repo includes two local suites for iterating on the fixture app:

examples/test-app/app/(tabs)/settings.tsx

@@ -19,6 +19,7 @@ export default function SettingsRoute() {
         onLoadDiagnostics={state.loadDiagnostics}
         onOpenAccessorySetup={() => router.push('/accessory-setup')}
         onOpenAutomationLab={() => router.push('/automation')}
+        onOpenHeavyFeed={() => router.push('/heavy-feed')}
         onOpenInertSurface={() => router.push('/inert')}
         onOpenSnapshotDepth={() => router.push('/snapshot-depth')}
         onOpenWebViewLab={() => router.push('/webview')}

examples/test-app/app/_layout.tsx

@@ -28,6 +28,7 @@ function RootLayoutContent() {
         <Stack.Screen name="inert" options={{ presentation: 'fullScreenModal' }} />
         <Stack.Screen name="snapshot-depth" />
         <Stack.Screen name="deep-tree" />
+        <Stack.Screen name="heavy-feed" options={{ headerShown: true, title: 'Heavy feed' }} />
         <Stack.Screen name="ticker" />
         <Stack.Screen name="perf-lab" />
         <Stack.Screen name="product/[productId]" />

examples/test-app/app/heavy-feed.tsx

@@ -0,0 +1,5 @@
+import { HeavyFeedScreen } from '../src/screens/HeavyFeedScreen';
+
+export default function HeavyFeedRoute() {
+  return <HeavyFeedScreen />;
+}

examples/test-app/src/route-params.ts

@@ -0,0 +1,10 @@
+export function clampInteger(
+  value: string | undefined,
+  fallback: number,
+  min: number,
+  max: number,
+): number {
+  const parsed = Number.parseInt(value ?? '', 10);
+  if (!Number.isFinite(parsed)) return fallback;
+  return Math.min(max, Math.max(min, parsed));
+}

examples/test-app/src/screens/DeepTreeScreen.tsx

@@ -1,6 +1,7 @@
 import { useLocalSearchParams } from 'expo-router';
 import { StyleSheet, Text, View } from 'react-native';
 
+import { clampInteger } from '../route-params';
 import { useAppColors, type AppColors } from '../theme';
 
 /**
@@ -62,12 +63,6 @@ function DeepLevel({
   );
 }
 
-function clampInteger(value: string | undefined, fallback: number, min: number, max: number) {
-  const parsed = Number.parseInt(value ?? '', 10);
-  if (!Number.isFinite(parsed)) return fallback;
-  return Math.min(max, Math.max(min, parsed));
-}
-
 function createStyles(colors: AppColors) {
   return StyleSheet.create({
     frame: {