add powerup functionality + interaction

Assets/Materials/GunMaterial.mat

Assets/Prefabs/HealthOrb.prefab

Assets/Prefabs/PowerOrb.prefab

Assets/Prefabs/SpeedOrb.prefab

Assets/Scripts/Managers/OrbManager.cs

Assets/Scripts/Orbs/HealthOrb.cs

Assets/Scripts/Orbs/PowerOrb.cs

Assets/Scripts/Orbs/SpeedOrb.cs

Assets/Scripts/Player/PlayerHealth.cs

Assets/Scripts/Player/PlayerPower.cs

Assets/Scripts/Player/PlayerSpeed.cs

Assets/_Complete-Game/Prefabs/Cat.prefab

Assets/_Complete-Game/Prefabs/Cat.prefab.meta

Assets/_Complete-Game/Prefabs/HealthOrb.prefab

Assets/_Complete-Game/Prefabs/HealthOrb.prefab.meta

Assets/_Complete-Game/Prefabs/PowerOrb.prefab

Assets/_Complete-Game/Prefabs/PowerOrb.prefab.meta

Assets/_Complete-Game/Prefabs/SpeedOrb.prefab

Assets/_Complete-Game/Prefabs/SpeedOrb.prefab.meta

Assets/_Complete-Game/Prefabs/stalkerNew.prefab