Add menu system and scene navigation

The changes include: - Moving script files to scripts/ directory -
Creating Start menu scene with Play/Quit buttons - Adding scene
switching between menu and gameplay - Creating theme for menu buttons -
Adding ESC key to return to menu

scripts/Paddle.gd

@@ -0,0 +1,25 @@
+extends CharacterBody2D
+
+const SPEED: float = 350.0
+
+@export var player_id: int
+@export var score_label: Label
+var score: int = 0
+
+func _input(event: InputEvent) -> void:
+  if event.is_action_pressed('up-%d' % player_id):
+    velocity = Vector2(0, -SPEED)
+  if event.is_action_pressed( 'down-%d' % player_id):
+    velocity = Vector2(0, SPEED)
+  if event.is_action_released('up-%d' % player_id) or \
+    event.is_action_released('down-%d' % player_id):
+    velocity = Vector2.ZERO
+
+func _physics_process(_delta: float) -> void:
+  move_and_slide()
+
+func increment_score():
+  # score one point
+  score += 1
+  # update the UI label
+  score_label.text = '%02d' % score

scripts/Paddle.gd.uid

@@ -0,0 +1 @@
+uid://d0dti6pba80ci

scripts/ball.gd

@@ -0,0 +1,31 @@
+extends CharacterBody2D
+
+const SPEED : float = 310.0
+
+@export var paddle_0 : Node2D
+@export var paddle_1 : Node2D
+
+
+func _ready() -> void:
+  initialize()
+
+func _physics_process(_delta: float) -> void:
+  var collision = move_and_collide(velocity * _delta)
+  if collision:
+    velocity = velocity.bounce(collision.get_normal())
+
+func initialize():
+  var extra_offset = 0.0 if randf() < 0.5 else PI
+  var angle = extra_offset + randf_range(-PI/3.0, PI/3.0)
+  velocity = Vector2(cos(angle), sin(angle)).normalized() * SPEED
+  position = get_viewport_rect().size / 2.0
+
+func _on_screen_exited() -> void:
+  #Update Score
+  if position.x <0.0:
+    paddle_1.increment_score()
+  else:
+    paddle_0.increment_score()
+  #Reint After 1 second
+  await get_tree().create_timer(1.0).timeout
+  initialize()

scripts/ball.gd.uid

@@ -0,0 +1 @@
+uid://wrequpaalk7f

scripts/gameplay.gd

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+extends Control
+
+func _ready():
+    set_process(true)
+
+func _process(_delta):
+   if Input.is_action_pressed("key_exit"):
+      get_tree().change_scene_to_file("res://scenes/Start.tscn")

scripts/gameplay.gd.uid

@@ -0,0 +1 @@
+uid://8lo33im7wrya

scripts/start.gd

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+extends Control
+func _ready():
+  %Button_Play.pressed.connect(play)
+  %Button_Quit.pressed.connect(quit_game)
+
+func play():
+  get_tree().change_scene_to_file('res://scenes/gameplay.tscn')
+
+func quit_game():
+  get_tree().quit()

scripts/start.gd.uid

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+uid://d3rocjpvkb3te