[Godot CRPG DevLog 2] Squad movement & Tactical mode

Welcome to my CRPG DevLog2! This milestone still focuses on unit movement:

1. Formation based movement of a three unit squad, currently only triangular formation is supported, others could be added later like old DND games
2. Squad member selection and single unit movement
3. Tactical mode toggle
4. Unit movement in tactical mode and unit turn wheel

There are still lots of issues about squad pathfinding, but it's ok for now, I'll improve it later. Next milestone will focus on adding unit status and basic fighting based on Action Points (AP).