[0.74] New app hangs on blank screen if dev server is not started

[huntie]

Description

Bug from at least 0.74.0-rc.2 (I've not yet confirmed when this was introduced).

Screen.Recording.2024-03-11.at.14.06.36-1.mov

Steps to reproduce

1. Install 0.74 RC2

   npx react-native@next init RN0740RC2 --version 0.74.0-rc.2

2. Run on iOS without starting the dev server.

React Native Version

0.74.0-rc.2

Affected Platforms

Runtime - iOS

Output of npx react-native info

System:
 OS: macOS 14.3
 CPU: (24) arm64 Apple M2 Ultra
 Memory: 1.99 GB / 128.00 GB
 Shell:
 version: "5.9"
 path: /bin/zsh
Binaries:
 Node:
 version: 18.18.2
 path: ~/.nvm/versions/node/v18.18.2/bin/node
 Yarn:
 version: 3.6.4
 path: ~/homebrew/bin/yarn
 npm:
 version: 9.8.1
 path: ~/.nvm/versions/node/v18.18.2/bin/npm
 Watchman:
 version: 2024-03-03T02:25:27Z
 path: /usr/local/bin/watchman
Managers:
 CocoaPods:
 version: 1.14.3
 path: /usr/local/bin/pod
SDKs:
 iOS SDK:
 Platforms:
 - DriverKit 23.2
 - iOS 17.2
 - macOS 14.2
 - tvOS 17.2
 - watchOS 10.2
 Android SDK: Not Found
IDEs:
 Android Studio: 2022.3 AI-223.8836.35.2231.10406996
 Xcode:
 version: 15.1/15C65
 path: /usr/bin/xcodebuild
Languages:
 Java:
 version: 17.0.8
 path: /Users/huntie/.jenv/shims/javac
 Ruby:
 version: 3.1.4
 path: /Users/huntie/homebrew/bin/ruby
npmPackages:
 "@react-native-community/cli": Not Found
 react:
 installed: 18.2.0
 wanted: 18.2.0
 react-native:
 installed: 0.74.0-rc.2
 wanted: 0.74.0-rc.2
 react-native-macos: Not Found
npmGlobalPackages:
 "*react-native*": Not Found
Android:
 hermesEnabled: true
 newArchEnabled: false
iOS:
 hermesEnabled: true
 newArchEnabled: false

Stacktrace or Logs

Blank screen

Reproducer

https://github.com/facebook/react-native/releases/tag/v0.74.0-rc.2

Screenshots and Videos

No response

[github-actions]

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