Provide connection info in the tool bar

It would be convenient to be able to quickly access important status information for the current connection (eg. user name, search path, date style, etc) from the top bar.

Start by locating the top-bar implementation and the code that provides the current connection state. Review how the username, search path, and date style are exposed, then determine the appropriate toolbar presentation. Done means the requested connection information is quickly accessible from the top bar.

Written by the indexing model from the issue text.