feat: allocate Metro ports for concurrent harness runs

[V3RON]

Summary

• add lock-backed Metro port fallback so concurrent Harness runs can move off a busy configured port before Metro and platform startup begin
• keep the resolved Metro port consistent through runtime setup, logging, and Jest global config, and surface a clear fallback or exhaustion message
• add tests for fallback, exhaustion, and iOS physical-device behavior plus a version plan describing the user-facing change

Validation

• pnpm vitest run packages/jest/src/tests/harness.test.ts packages/jest/src/tests/metro-port.test.ts packages/platform-ios/src/tests/instance.test.ts packages/platform-android/src/tests/instance.test.ts
• pnpm nx test jest

[vercel]

The latest updates on your projects. Learn more about Vercel for GitHub.

Project	Deployment	Actions	Updated (UTC)
react-native-harness	Ready	Preview, Comment	Apr 3, 2026 0:50am