Update Community CLI Flow types (#49866)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/49866

Scope down type definitions to the subset of CLI we are currently explicitly referencing. Rename/bump to `19.x`.

Related to:
- https://github.com/facebook/react-native/pull/45380
- https://github.com/react-native-community/cli/pull/2584
- (others)

Changelog: [Internal]

Reviewed By: rshest

Differential Revision: D70699083

fbshipit-source-id: 43af1b529d9b95f3d8ba955588af6a09367cdcea