Add sandbox game mode

The sandbox mode would allow players to tweak and change different aspects of the game to make the game more personal. Could be unlocked after beating Subnautica 2 once.

For example change AI patterns of wildlife, adjust various ressource respawn,adjust base hunger/drink rate, night/day length, and so on.

The variables ,which alter the different aspects,would be grouped in categories to make adjusting the game mode more convenient.

It would basically be like debug mode but more limited and based on sandbox mode in games like V Rising, Project Zomboid.

This would also be an ideal first step & learning experience before trying to mod the game.

I like this, it’d allow players to make the game easier or harder for themselves however they see fit.