Add descriptions of stages

As someone interested in projects, I want to know what these "stages" mean. What's bootstrapping mean? What's the difference between drifting and hibernating?

Descriptions should be added to:

[ ] The Projects filtering sidebar
[ ] The "status bar" that each project has

Start at the Projects filtering sidebar and each project's status bar, then trace where stage labels such as bootstrapping, drifting, and hibernating are rendered. Done means both locations explain each stage, including the distinction between drifting and hibernating.

Written by the indexing model from the issue text.