Feature Request: Migration Command

[MichaelGoberling]

Is your feature request related to a problem? Please describe.
It is easy to accidentally initialize an application as a Standalone Application when starting out with App Builder and applications of these types cannot be viewed in Adobe Experience Cloud.

Describe the solution you'd like
A new CLI command should be introduced to handle migrating between these two versions of applications. Suggestion: aio app migrate.

The command could inspect the user's working directory and generate a list of application types eligible for migration. For now, the only option would be to go from Standalone Application to DX Experience Cloud SPA v1.

Describe alternatives you've considered
The migration can be performed manually, but it is a tedious process, especially if the application has already been published. This will provide a huge QoL adjustment for users.

[aiojbot]

JIRA issue created: https://jira.corp.adobe.com/browse/ACNA-1685