Automatic Code Migrations

## Goal Description

Be able to automatically update a code base from one version of Bevy to the next one

This goal is an experimentation to check how far we can go, or if it's just not possible

## Goal Status

This is a potential [Bevy Project Goal](https://bevy.org/learn/contribute/project-information/project-goals/). Its state on the [Project Goals Board](https://github.com/orgs/bevyengine/projects/23/views/1) determines if it is Proposed, Postponed, Blocked (Approved), Inactive (Approved), Active (Approved), Completed, or Declined.

- **Staffing SMEs**: @mockersf
- **Working Group Link**: [link](https://discord.com/channels/691052431525675048/1525601738969583646)
- **Design Documents**: [Draft](https://hackmd.io/@bevy/HkXtxqV0-x)