Implement health bar system: add HealthBar class for managing health, integrate health updates in HUDLayer, and modify enemy attack handling to reflect damage taken.

game/weapons/blade_of_recursion.rb

@@ -0,0 +1,30 @@
+class BladeOfRecursion
+  def initialize
+    @damage = 1
+    @range = 200
+    @speed = 500
+    @x = 0
+    @y = 0
+    @direction = nil
+  end
+
+  def attack(direction)
+    @direction = direction
+    @x, @y = $bus.get(:player_position)
+  end
+
+  def update(dt)
+    return unless @direction
+
+    @x += Math.cos(@direction) * @speed * dt
+    @y += Math.sin(@direction) * @speed * dt
+
+    $bus.get(:attack, @x, @y, @range, @damage)
+
+    # If the blade has traveled its max range, reset it
+    player_x, player_y = $bus.get(:player_position)
+    if Math.hypot(@x - player_x, @y - player_y) > @range
+      @direction = nil
+    end
+  end
+end