chore: bump example and dev deps to React Native 0.85.3

[janicduplessis]

Summary

Brings the example app and root dev dependencies up from React Native 0.80.1 to 0.85.3 (current latest stable). Useful for testing against current RN releases — e.g. validating reports like #691 which are filed against 0.82+.

Notable changes:

• example/package.json: react-native 0.80.1 → 0.85.3, react 19.1.0 → 19.2.6, react-native-test-app 4.x → 5.x (new major; still supports RN 0.76–0.85), @react-native/{babel-preset,eslint-config,metro-config,typescript-config} → 0.85.3, @types/react → 19.x, @react-native-community/cli → 20.x, react-native-screens → 4.25.x, react-native-gesture-handler → 2.31.x.
• package.json (root): matching bumps for @react-native/babel-preset, @react-native/eslint-config, @react-native/eslint-plugin-specs, react, react-dom, react-native, react-test-renderer. Adds @react-native/jest-preset and points the Jest preset at it — the RN Jest preset moved to a separate package in 0.85.

No source code changes. Existing 3 ESLint deep-import warnings (@react-native/no-deep-imports on codegenNativeComponent and TurboModuleRegistry) are unchanged; they exist on main today and don't fail lint.

Test Plan

• yarn install in root and example/ — both clean.
• yarn test (format:check + validate:eslint + validate:typescript + validate:jest) — green; 13/13 Jest tests pass.
• bob build (via prepare) — builds commonjs / module / typescript targets cleanly.
• CI matrix on this PR validates Android + iOS builds against the bumped RN version.