Add Levels and Leveling to DungeonBots

[bofirial]

Every DungeonBot should start at Level 1. After completing an Adventure for the first time the DungeonBot should earn Experience. When the DungeonBot receives sufficient Experience they should Level up. This will allow the DungeonBot to increase their statistics as they see fit and also occasionally select new Abilities.

[bofirial]

DungeonBots should be allowed to pick one of 2 abilities when they reach certain levels. The character screen should give them a button in the Ability section that displays a modal for them to choose?

Or maybe no modal because the character screen should be used as a modal when the character levels???