bluesky-social/social-app ? reverse-engineered prompt

Build me a social media app that's a lot like Bluesky or Twitter. It needs to work on the web, on iOS, and on Android.

The core features should be simple: users can create an account, make a profile, follow other people, and see a feed of short posts from the accounts they follow. I want this to be built as a cross-platform app, probably using React Native and TypeScript so we can share most of the code between the web and mobile versions.

The app should be designed to connect to an open, decentralized social network like the AT Protocol that Bluesky uses. Most importantly, please structure the project so that I can easily fork it and change the branding later on—I want to be able to add my own name, logo, and color scheme without having to rewrite everything.