test(platform): extract Apple perf and Android runtime fixtures (#2253)

* test(platform): extract shared fixtures from the Apple perf and Android runtime suites

Move the duplicated host-command routing, app-bundle writers, and ps
handlers behind packages/platform-apple/src/core/__tests__/perf.fixtures.ts,
and the Android runtime host, device, and ordinary-bind builders behind
packages/platform-android/src/runtime.fixtures.ts. Every test keeps its
title and its own assertions; test and assertion counts are unchanged.

* chore(gates): exclude .fixtures.ts modules from changed-line coverage

runtime.fixtures.ts (packages/platform-android/src) sits outside any
__tests__ dir, so vitest's coverage.include picked it up as production
source and the changed-line gate scored its 20 unreachable construction
lines directly, failing at 39.39% against the 70% threshold.

Add '**/*.fixtures.ts' to coverage.exclude (repo-wide convention:
40+ fixture modules, all test support, never production). The file
disappears from lcov and scripts/coverage-changed/model.ts's existing
excluded-path fallback reports it non-gating instead, with no
duplicate classifier needed there.

Planted red (targeted run against the real diff/model, not committed):
BEFORE (file present in lcov, all added lines uncovered): totalLines=110
coveredLines=0 pct=0 passed=false. AFTER (file absent from lcov post-fix):
totalLines=0 excludedTotal=99 excludedReason=excluded-path passed=true.
Confirmed against a real `vitest run --coverage` + `check:coverage-changed`
pass: runtime.fixtures.ts absent from coverage/lcov.info, gate PASS,
99 lines reported under excluded/excluded-path.

Author: thymikee

packages/platform-android/src/runtime.fixtures.ts

@@ -0,0 +1,110 @@
+import type { AndroidClipboardShellSupport } from '@agent-device/contracts/android-clipboard-support';
+import type { DeviceBinding } from '@agent-device/contracts/platform-runtime';
+import type {
+  PlatformRuntimeHost,
+  PlatformRuntimeOperations,
+  PlatformRuntimeOwner,
+} from '@agent-device/contracts/platform-runtime-operations';
+import type { DeviceInfo } from '@agent-device/kernel/device';
+
+export const ANDROID_EMULATOR: DeviceInfo = {
+  platform: 'android',
+  id: 'emulator-5554',
+  name: 'Android',
+  kind: 'emulator',
+  target: 'mobile',
+  booted: true,
+};
+
+export const UNKNOWN_KIND_DEVICE = {
+  ...ANDROID_EMULATOR,
+  kind: 'unknown',
+} as unknown as DeviceInfo;
+
+const audioProbeHost: PlatformRuntimeHost['audioProbe'] = {
+  hostCapture: {
+    info: {
+      source: 'system-audio',
+      backend: 'fixture',
+      sourceCount: 0,
+      notes: () => [],
+    },
+    start: async () => {
+      throw new Error('Audio probe is outside this runtime fixture.');
+    },
+    inspectProcess: async () => 'missing',
+    terminateProcess: async () => 'already-missing',
+  },
+  web: { resolve: async () => undefined },
+  ownedProcesses: { replace: () => {}, clear: () => {} },
+};
+
+export const emptyAppInventory = {
+  apple: { listApps: async () => [] },
+  android: { listApps: async () => [] },
+  harmonyos: { listApps: async () => [] },
+};
+
+const emptyAppState = {
+  android: { run: async () => ({ stdout: '' }) },
+  harmonyos: { run: async () => ({ stdout: '' }) },
+};
+
+function localAndroidScreenRecording() {
+  return {
+    mode: 'local' as const,
+    start: async () => {
+      throw new Error('unused');
+    },
+    signal: async () => true,
+    isRunning: async () => false,
+    exists: async () => false,
+    pull: async () => ({ stdout: '', stderr: '', exitCode: 0 }),
+    remove: async () => true,
+    readManifest: async () => undefined,
+    writeManifest: async () => {},
+    removeManifest: async () => {},
+  };
+}
+
+/** The smallest host the Android runtime binds against; `overrides` replace whole facets. */
+export function androidRuntimeHost(overrides: Record<string, unknown> = {}): PlatformRuntimeHost {
+  return {
+    androidTools: { probeClipboardShellSupport: async () => 'supported' as const },
+    processTransports: { resolve: async () => ({ mode: 'local' as const }) },
+    appInventory: emptyAppInventory,
+    localInteractors: { resolve: async () => ({}) },
+    audioProbe: audioProbeHost,
+    screenRecording: { android: { resolve: async () => localAndroidScreenRecording() } },
+    ...overrides,
+  } as unknown as PlatformRuntimeHost;
+}
+
+/** A host with app state and device readiness, so navigation and clipboard cells can bind. */
+export function androidNavigationHost(
+  probeClipboardShellSupport: () => Promise<AndroidClipboardShellSupport> = async () => 'supported',
+): PlatformRuntimeHost {
+  return androidRuntimeHost({
+    androidTools: {
+      probeClipboardShellSupport,
+      runAdb: async () => ({ stdout: '', stderr: '', exitCode: 0 }),
+    },
+    appState: emptyAppState,
+    deviceReadiness: { android: { ensureReady: async (selected: DeviceInfo) => selected } },
+  });
+}
+
+export async function bindOrdinary(
+  runtime: PlatformRuntimeOwner,
+  device: DeviceInfo,
+): Promise<DeviceBinding<PlatformRuntimeOperations>> {
+  return await runtime.bind({
+    device,
+    intent: { kind: 'ordinary' },
+    scope: {
+      signal: new AbortController().signal,
+      diagnostics: { emit: () => {} },
+      progress: { report: () => {} },
+    },
+  });
+}