Docs: Clarify APIs of Controls doc block/addon/argTypes

[kylegach]

Closes #22600

What I did

• Add callouts to Controls doc block API reference
  • @storybook/addon-controls must be registered
  • How to configure what
    • Controls blocks in docs pages: this API
    • Controls in addons panel: Controls addon
    • Individual controls: argTypes

How to test

1. Follow the steps in the contributing instructions for this branch, api-ref-doc-block-controls-install-addon

Checklist

• Make sure your changes are tested (stories and/or unit, integration, or end-to-end tests)
• Make sure to add/update documentation regarding your changes
• If you are deprecating/removing a feature, make sure to update
  MIGRATION.MD

Maintainers

• If this PR should be tested against many or all sandboxes,
  make sure to add the ci:merged or ci:daily GH label to it.
• Make sure this PR contains one of the labels below.

["cleanup", "BREAKING CHANGE", "feature request", "bug", "documentation", "maintenance", "dependencies", "other"]

[jonniebigodes]

Thanks for taking care of this one. Appreciate it 🙏 ! Looks good on my end.

[kylegach]

This is docs-only and all docs-related checks have passed, so I'm going to merge with failing checks.

[jonniebigodes]

Self-merging as this is docs related item.