Setup a Rails Repository to work in VSCode and write setup documentation

I have an existing Rails 6 repository that has additional components (like Redis and MySQL 5). I would like the project to work properly in VS Code with remote containers and then have step-by-step documentation on how a new dev can get this up and running on both an M1 MBP and non-M1 MBP (Macbook Pro).

Deliverables:
- README file updated explaining how to get this app running
- Changes to the app that allow it to run in VS Code for development on MBPs (M1 and non-M1)
- Ensuring that a new developer can get a new dev environment up and running by following instructions

If everything goes well with this, I also have some additional work:
- Upgrading to Ruby 3.0
- Upgrading to Rails 7
- Building out some Postman collections for easier development and testing
- Build out factories for testing/staging data
- Build out testing framework
- Setup Mailgun in staging/production
- Setup Redis/Resque for background jobs
- Create caching system for better performance with remote DB