Added Boss Attack Patterns

• The boss now has set types of attacks that are determined based on which attack "phase" the boss is in. 
• There are three types of attacks:
  • Attack 1: this is a basic projectile attack. They are spawned randomly and move forward.
  • Attack 2: this is a smarter projectile attack. They are spawned at a single point but move towards the player's position.
  • Attack 3: this is a charge attack that does more damage but is more choreographed and easier to dodge.
• Each phase will also generate text above the boss to instruct the player on what to do. 
• There are 7 phases:
  • In phase 0, the intro song plays and the player can move around but cannot attack. After 16 beats, phase 1 will begin.
  • In phase 1, the verse song plays on loop. The boss begins to attack with Attack 3 and the player must dodge them. After 32 beats, phase 2 will begin.
  • In phase 2, the players may now press J and K to fight back.  The boss uses Attack 1. When the boss health reaches 90 or below, phase 3 begins.
  • In phase 3, the player is taught how to hit a heavy attack combo.  The boss uses Attack 1 but projectiles move faster. When the boss health reaches 75 or below, phase 4 begins.
  • In phase 4, the player is taught the shield combo. The boss uses Attack 2. When the boss health reaches 20 or below, phase 5 begins.
  • In phase 5, the bus attacks become much faster and harder to dodge. The boss uses Attack 2 but projectiles move a lot faster. When the boss health reaches 0 or below, phase 6 begins.
  • In phase 6, a text will appear that says "The bus has been defeated!". 

System Changes

• Reduced the number of inputs required for combos from 3 --> 2 because it was too difficult to reliably pull off.
• Removed the "L" key from the combo inputs. This means that combos only consist of "J" and "K" keys.
• Audio tracks now change based on the attack phase of the boss.
• Added a "You have been defeated!" message that appears when Lucy runs out of HP.

Tweaks and Adjustments

• Player basic attack damage changed from 2 --> 1.
• Changed the functions that were responsible for creating boss projectiles so that they can now take in a parameter that controls attack frequency. This allows more customizability for the difficulty when creating the boss attack patterns. 
• Changed the bus charge attack so it can repeat itself in set intervals, instead of only happening once. 

Bug Fixes

• Fixed an issue where the pause screen would show up when the player or the bus dies.