[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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