Reorganize APIs section of the docs to focus on Minimal APIs

[mikekistler]

The "APIs" section of the ASP.NET Core docs should be reorganized to focus on the Minimal APIs content.

The current APIs section looks like this:

Specific changes requested:

• All the articles currently within the "Minimal APIs" section should be move up to be directly under "APIs".
• The current "APIs/Overview" article should be merged with the "Minimal APIs/Overview" article, with clear guidance added to guide users toward Minimal APIs for new projects.
• Where practical, content for controllers should be merged into the articles for Minimal APIs, following the pattern used in the OpenAPI sections. A top candidate here is the "Handle errors" article.
• The "Controller-based APIs" section should be moved to the bottom of the "APIs" section.

[The following was added by wadepickett]
Related to: #35741

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Associated WorkItem - 480868