Check if the native extension is installed

In order to notify the user of the requirement to install the native companion we should check if it is installed.
Maybe we do this in the status call?

If the companion is NOT installed and the user tries to connect to a Tor connection we can then show a message to install the companion.

Start by tracing the status call and the connection flow for a Tor connection in the browser extension. Determine where the native companion's installation state can be checked and where a user-facing message belongs. Done means an uninstalled companion is detected and the user is prompted when attempting a Tor connection.

Written by the indexing model from the issue text.