Impact-I/reFlutter ? reverse-engineered prompt

Build me a Python tool for Flutter app reverse engineering that can take an APK or IPA, patch the bundled Flutter engine, and repack the app so it can be run again with extra visibility. I want it to help with traffic interception, bypass some Flutter certificate pinning, and dump useful runtime info like classes, functions, strings, fields, and code offsets into a file I can pull from the device.

It should support Android and iOS for the stable and beta Flutter engines, and it would be great if it can also work with Frida for dynamic analysis using the offsets it finds. Please include a simple command line flow, a Docker based build option for custom engine patching, and clear output that tells me the snapshot hash and the rebuilt app file.

If you need to check current Flutter or Frida docs while implementing it, go ahead and look them up online.