Extension to Functions Codebase & npm Package Migration

Overview

This skill guides the agent in migrating a Firebase Extension repository or instance into either:

1. A standalone Cloud Functions for Firebase codebase (firebase-functions, for end-user app integration), or
2. A publishable npm package / shareable open source package (for extension publishers distributing reusable V2 functions).

It leverages native Cloud Functions for Firebase GA capabilities to handle permissions, dependencies, and lifecycle hooks natively in code, and provides instructions for modernizing legacy V1 triggers to V2 using the Destructuring Compatibility Shim.