[iOS] `multiline` TextInput in ScrollView scrolls to top of TextInput if when typing overflows to a new line

Description

When typing in a multiline TextInput (controlled in this case), the screen scrolls so the entire TextInput is within the view when the text overflows to the next line. Only happens if the user is typing at the end of the text. See the demos below.

Similar to but not quite the same as #48412 and #39660

Steps to reproduce

1. Have a (controlled, but not sure it matters) multiline TextInput within ScrollView with some lines of text in it
2. Scroll down so the top of the TextInput is above the viewport
3. Start typing at the end of the text within the TextInput - when the text overflows to a new line the top of the element will automatically scroll back into the viewport

React Native Version

0.76, 0.74.5

Affected Platforms

Runtime - iOS

Output of npx react-native info

System:
  OS: macOS 14.6.1
  CPU: (12) arm64 Apple M3 Pro
  Memory: 113.59 MB / 18.00 GB
  Shell:
    version: "5.9"
    path: /bin/zsh
Binaries:
  Node:
    version: 20.16.0
    path: ~/.nvm/versions/node/v20.16.0/bin/node
  Yarn:
    version: 1.22.22
    path: /opt/homebrew/bin/yarn
  npm:
    version: 10.8.1
    path: ~/.nvm/versions/node/v20.16.0/bin/npm
  Watchman:
    version: 2024.08.19.00
    path: /opt/homebrew/bin/watchman
Managers:
  CocoaPods:
    version: 1.15.2
    path: /Users/uakin/.rbenv/shims/pod
SDKs:
  iOS SDK:
    Platforms:
      - DriverKit 24.1
      - iOS 18.1
      - macOS 15.1
      - tvOS 18.1
      - visionOS 2.1
      - watchOS 11.1
  Android SDK: Not Found
IDEs:
  Android Studio: 2024.1 AI-241.18034.62.2411.12169540
  Xcode:
    version: 16.1/16B40
    path: /usr/bin/xcodebuild
Languages:
  Java:
    version: 17.0.12
    path: /usr/bin/javac
  Ruby:
    version: 3.0.7
    path: /Users/uakin/.rbenv/shims/ruby
npmPackages:
  "@react-native-community/cli": Not Found
  react:
    installed: 18.2.0
    wanted: 18.2.0
  react-native:
    installed: 0.74.5
    wanted: 0.74.5
  react-native-macos: Not Found
npmGlobalPackages:
  "*react-native*": Not Found
Android:
  hermesEnabled: true
  newArchEnabled: false
iOS:
  hermesEnabled: true
  newArchEnabled: false

info React Native v0.77.0 is now available (your project is running on v0.74.5).
info Changelog: https://github.com/facebook/react-native/releases/tag/v0.77.0
info Diff: https://react-native-community.github.io/upgrade-helper/?from=0.74.5
info For more info, check out "https://reactnative.dev/docs/upgrading?os=macos".

Stacktrace or Logs

N/A

Reproducer

https://snack.expo.dev/hUmMl37uriVOWz7jHP0jW

Screenshots and Videos

Scrolls so the beginning of the element is in view, behaves normally otherwise:

https://github.com/user-attachments/assets/758471dd-a45a-4134-9a8c-940bfb20e5aa

Only happens when typing at the end of the text (also adding a new line won't trigger the same behaviour):

https://github.com/user-attachments/assets/ccdd16f4-c293-4177-97e0-098d111ada26

Even weirder when the TextInput is long enough to cover the entire screen - will scroll to the top and then scroll back to bottom so cursor is within the screen:

https://github.com/user-attachments/assets/375267fc-cd0b-436e-a794-717a92216bfb

リンクされた Snack 再現コードから始め、iOS でテキストの末尾に入力しているときの ScrollView 内の複数行 TextInput を比較します。自動スクロールに関係する TextInput と ScrollView の動作を追跡し、そのうえで、新しい行にあふれたときにカーソルを表示したまま TextInput の上端が表示領域内にスクロールされなくなっていることを確認します。