Add more fish/huntable AI

Given the diverse roster of semi-aquatics that are currently in the game, there is a very noticeable lack of fish in the lakes of Panjura. On top of this, the fish in any given lake only respawn when there are at least two fish already present.

Each sizeable body of water should have a base level of 5-6 fish at all times, with larger lakes like Spined Lizard Lagoon and the Massive lake in the center of the map containing a base level of 20+ fish.