Add codegen for MixedType diffing (#52266)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/52266

Native components may use `MixedType` properties in rare cases to hold untyped data. This diff adds support for serializing and prop diffing these types of props so that all of the props and object fields would be included in prop diffing results.

Changelog: [Internal]

Reviewed By: mdvacca

Differential Revision: D77307169

fbshipit-source-id: ae6b00207ef857c9cfa4bdf9c235972915410a29