[Fabric]: Performance Tests for React Native Windows

[iamAbhi-916]

Description

Performance testing framework for RNW Fabric components.
Each test measures mount, unmount, re-render and component specific test scenario times also records baselines via snapshot matching.

How to Run

cd packages/e2e-test-app-fabric
yarn perf                                              # all tests
yarn perf -- --testPathPattern=FlatList                 # single component
yarn perf:update                                       # update all baselines
yarn perf:update --testPathPattern=TouchableHighlight   # update one baseline

CLI Generator

yarn perf:create -- --name=ComponentName scaffolds a new .perf-test.tsx file with the correct structure, required props detection, and category selection.

Type of Change

• New feature (non-breaking change which adds functionality)

Why

RNW Fabric had no automated way to catch render performance regressions in core components.

Resolves #15665

What

Refer this wiki : https://github.com/microsoft/react-native-windows/wiki/Performance-tests-Fabric

Screenshots

Testing

Tested locally, mock ran as CI

Changelog

Should this change be included in the release notes: yes

Add a brief summary of the change to use in the release notes for the next release.
Added @react-native-windows/perf-testing, a component performance testing framework for RNW Fabric

Microsoft Reviewers: Open in CodeFlow