feat(rules,skills): add React Native / Expo rules pack and react-native-patterns skill (#2275)

* feat(rules,skills): add React Native / Expo rules pack and react-native-patterns skill

* fix(rules,skills): address review feedback — safeParse nav example, drop deprecated sentry-expo, memoize list renderItem, clarify New Architecture SDK support

* fix(rules,skills): drop deprecated Flipper, surface permission-denied state in location hook

rules/react-native/testing.md

@@ -0,0 +1,52 @@
+---
+paths:
+  - "**/*.ts"
+  - "**/*.tsx"
+---
+# React Native / Expo Testing
+
+> This file extends [common/testing.md](../common/testing.md) with React Native / Expo specific content.
+> Coverage target and TDD workflow are inherited from common/testing.md (80% minimum, RED-GREEN-REFACTOR).
+
+## Tooling
+
+| Layer | Tool |
+|-------|------|
+| Unit / component | Jest + `@testing-library/react-native` (via `jest-expo` preset) |
+| Hooks | `@testing-library/react-native` `renderHook` |
+| E2E | Maestro (recommended, simple YAML flows) or Detox |
+| Type safety | `tsc --noEmit` in CI |
+
+## Component Tests
+
+- Query by accessible role/label/text, not by `testID` unless necessary — this also enforces accessibility.
+- Assert on user-visible behavior, not implementation details.
+- Follow Arrange-Act-Assert.
+
+```tsx
+import { render, screen, fireEvent } from '@testing-library/react-native'
+
+test('calls onSelect with the user id when pressed', () => {
+  const onSelect = jest.fn()
+  render(<UserCard user={{ id: '1', email: 'a@b.com' }} onSelect={onSelect} />)
+
+  fireEvent.press(screen.getByText('a@b.com'))
+
+  expect(onSelect).toHaveBeenCalledWith('1')
+})
+```
+
+## Mocking
+
+- Mock Expo SDK modules (camera, location, notifications, secure-store) at the test boundary.
+- Wrap components that use TanStack Query in a `QueryClientProvider` with a fresh client per test.
+- Mock navigation (`expo-router`) so screens render in isolation.
+
+## E2E
+
+- Cover critical flows only: auth, primary navigation, core transactions.
+- Run E2E on CI against a built app (EAS Build) before release.
+
+## What to test first
+
+Use the `tdd-guide` agent proactively for new features: write a failing test that captures the behavior, then implement.