Implements modifier system for weapons

Adds a modifier system allowing dynamic modification of weapon
stats and behavior. This includes:

- Creating ModifierLibrary to manage available modifiers.
- Adds ModifierManager to handle equipping and unequipping modifiers
- Adds a new RangedWeaponComponent to handle firing projectiles and
  managing modifiers.
- Introduces a DebugUI for in-game modifier management.
- Introduces an "Unlimited Power" modifier that changes the projectile scene.
- Modifies stats components to work with the new modifier system.

This system allows for more flexible and customizable weapon
functionality.

assets/themes/main_theme.tres

@@ -0,0 +1,16 @@
+[gd_resource type="Theme" load_steps=2 format=3 uid="uid://ddgipwj5yd0vw"]
+
+[sub_resource type="StyleBoxFlat" id="StyleBoxFlat_6ioqn"]
+bg_color = Color(0.6, 0.6, 0.6, 0.560784)
+border_width_left = 1
+border_width_top = 1
+border_width_right = 1
+border_width_bottom = 1
+border_color = Color(0.888331, 0.274714, 0.539223, 1)
+corner_radius_top_left = 3
+corner_radius_top_right = 3
+corner_radius_bottom_right = 3
+corner_radius_bottom_left = 3
+
+[resource]
+Button/styles/pressed = SubResource("StyleBoxFlat_6ioqn")