Use Hermes V1 as default engine (#54989)

Summary:
This change makes Hermes V1 the default engine for React Native for both platforms. This change needs to land before the branch cut of react native 0.84

bypass-github-export-checks

## Changelog:
[iOS][Changed] - Make Hermes V1 the default engine for iOS

Pull Request resolved: https://github.com/facebook/react-native/pull/54989

Test Plan:
1. Run `bundle exec pod install` and verified that Hermes V1 is used when building from source
<img height="480" alt="Simulator Screenshot - iPhone 17 Pro - 2025-12-29 at 11 28 44" src="https://github.com/user-attachments/assets/0889f16c-f2ee-4a0e-9a4d-529dd82c8283" />
2. Run `prebuild-ios -s` and verified that the scripts downloads the Hermes V1 tarball
<img width="831" height="324" alt="Screenshot 2025-12-29 at 10 37 53" src="https://github.com/user-attachments/assets/9a60565e-1e13-4967-a4a4-dd079e6b040f" />
3. GHA and nightlies

Reviewed By: vzaidman, cortinico, huntie

Differential Revision: D89881943

Pulled By: cipolleschi

fbshipit-source-id: 958b6d31bd4230ba4a5c7fee2bffc19e03dcbc89