Prototype 2 Build 0004

The main changes in this build are:

• Engine updated to Godot 4.0 Stable
• Replaced droid movement and control with a proper state machine - still needs work though
• Building construction is now working (not yet used for the Power Relay or Alament Refinery)
• Replaced several placeholder buildings with models created in Blender, but most of them still need work
• Objectives are working and, if applicable, trigger new objectives on completion
• Various in-game UI improvements
• Added player profile and preferences (preferences are saved per profile)
• Added character selection when starting a new game
• Buttons for game speed - but be careful when the temperature is very high or very low
• Proper day/night cycle