Group groups screen explanation of the icons and numbers

What do the icons and the numbers mean in the circles on the? Why are some circles solid while others use a dotted/dashed line?

We need a way to tell or remind the app uses what these mean.

Start at the Group groups screen in the React Native app and locate the code that renders the circles. Determine what the icons, numbers, and solid or dashed styles represent, then add an in-app explanation and verify that it is visible on that screen.

Written by the indexing model from the issue text.