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.

entities/scripts/stats_component.gd

@@ -31,14 +31,14 @@ var base_stats: Dictionary[String, Variant] = {
 	}
 }
 
-var stats: Dictionary
+var stats: Dictionary = {}
 
 func _init() -> void:
 	if not stats:
 		reset_stats()
 
 func reset_stats() -> void:
-	stats = base_stats.duplicate()
+	stats = base_stats.duplicate(true)
 	Log.pr("StatsComponent reset to base stats")
 
 func get_stat(stat_name: String) -> Variant:
@@ -92,4 +92,4 @@ func set_nested_stat(path: String, value) -> bool:
 
 	# Set the value at the final key
 	current[final_key] = value
-	return true
+	return true