[RFE] Add recommended targets to Archetypes

[rromannissen]

In large scale migration projects, it is often important to provide guidance for developers on what could be the most suitable migration path for a given application based on its taxonomy. Since archetypes have become a first class entity to classify applications in different types or categories, it makes sense to associate those recommendations with them. At a very high level, this enhancement would include the following:

• Allow architects to associate recommended migration targets to a given archetype, including custom migration targets.
• When analyzing a single application, the UI would highlight the recommended migration targets somehow, but it would still be up to the user to decide which should be selected.
• When analyzing multiple applications, recommended targets will only be highlighted if all applications belong to the same archetype.

This enhancement would be especially interesting for the Backstage/Janus integration use case, as it would allow organizations to enforce certain migration paths from their IDP. For that case:

• Discovery analysis would be automatically run on the application.
• Based on that discovery, the application would likely be associated with an archetype.
• Based on the archetype, the user would be presented (maybe only) with the recommended migration paths for analysis.

[rromannissen]

@dymurray @jortel @JustinXHale for your consideration

[JustinXHale]

Figma

[dymurray]

Closing as duplicate of #186