Status Package: Add additional checks

In working on https://github.com/Automattic/jetpack/pull/13698, our Status package has development mode, but does not check if a Jetpack connection is active, if we have confirmed the TOS, etc. We should add more of these checks over to help when non-Jetpack plugins use some of our packages and tools.

Read the Status package and the context in pull request 13698, then inventory the existing development-mode checks. Determine which Jetpack connection and TOS checks are required for non-Jetpack consumers; done means the Status package exposes the agreed additional checks with coverage for their relevant states.

Written by the indexing model from the issue text.