🚀 app-sdk monorepo

[lkostrowski]

SDK will likely need monorepo, because:

1. It provides code both for node and browser, having them in single package causes errors already (index file exposes fs, causing broken imports in browser)
2. It will likely expand with many connections to 3rd party and frameworks - Next.js specific, Remix specific, React specific

We can introduce monorepo with example packages:

1. sdk/core - typings and some basic symbols
2. sdk/next - Next adapters for handers
3. sdk/remix - like Next but for Remix
4. sdk/react - UI helpers
5. sdk/app-bridge - App bridge

etc