add CI for old arch

[ShiCheng-Lu]

No description provided.

[Copilot]

Pull Request Overview

This PR adds Continuous Integration (CI) support for React Native's old architecture by creating new CI jobs that test the application with the old architecture configuration disabled.

• Adds android-oldarch and ios-oldarch CI jobs that mirror existing Android and iOS jobs
• Implements automatic old architecture configuration by modifying the app.json file to set newArchEnabled to false
• Updates the build pipeline to test both new and old React Native architectures

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