This merge request involves a comprehensive refactor of the existing codebase governing the artificial intelligence (AI) behaviors of in-game enemies within our Unity game. The primary objective is to enhance the flexibility and maintainability of the AI system by implementing a Hierarchical Finite State Machine (HFSM). This architectural shift allows for the seamless integration of nested states and provides access to previous states, particularly beneficial for actions requiring historical context.

## Details

### Code Modification

The primary focus of this refactor involves migrating from the current state management approach to a more sophisticated Hierarchical Finite State Machine.

Utilized the UnityHFSM library (https://github.com/Inspiaaa/UnityHFSM) as a foundational framework for building the HFSM.

#### State Machine Creation

Initialized the state machine by instantiating a StateMachine object.

fsm = new StateMachine();

#### State Addition

Added states to the state machine using the AddState method. Each state is represented by a StateBase object, allowing the utilization of built-in state classes or custom classes inheriting from StateBase for defining state logic.

fsm.AddState(
    name,
    new State(
        onEnter,
        onLogic,
        onExit
    )
);

#### Transition Handling

Established transitions using TransitionBase objects, defining conditions for state transitions. This includes the option to use built-in transition types or create custom transition classes by inheriting from TransitionBase.

fsm.AddTransition(new Transition(
    from,
    to,
    condition
));

#### Initialization

Set the initial state and initialized the state machine to prepare for execution.

fsm.SetStartState(id);
fsm.Init();

#### Executio

Integrated the state machine into the game's update loop for continuous logic processing.

    void Update() {
        fsm.OnLogic();
    }