Add entries other than those in the command list

It should be possible to add commands (or even phrases, such as "How do you fly?") to the DB, not just those in the hard-coded list.

Start by locating the hard-coded command list and the code that writes commands to the DB. Trace how command lookup currently works, including whether phrases such as "How do you fly?" are supported. Done means users can add entries outside the built-in list and those entries can be stored and retrieved reliably.

Written by the indexing model from the issue text.