feat: Add core player input, movement, and special ability management systems with new UI components.

scripts/managers/player_input_manager.gd

@@ -114,22 +114,29 @@ func handle_unhandled_input(event):
 		
 		# Unified check for PowerUp keys
 		if ek == key_p1:
-			player.activate_powerup(0) # FASTER_SPEED
-		elif ek == key_p2:
-			if is_sng:
-				player.activate_powerup(3) # Ghost for SNG P2
-			else:
-				player.activate_powerup(2) # Wall for Normal P2
-		elif ek == key_p3 and not is_sng:
-			player.activate_powerup(1) # AREA_FREEZE
-		elif ek == key_p4 and not is_sng:
-			player.activate_powerup(3) # INVISIBLE_MODE
+			# Single Slot Logic: Find whatever powerup is currently set to 'true' and activate it
+			var active_effect = -1
+			if player.special_tiles_manager:
+				for effect_key in player.special_tiles_manager.inventory:
+					if player.special_tiles_manager.inventory[effect_key]:
+						active_effect = effect_key
+						break
 			
-		# Non-Remappable variants (Numpad) - Optional fallback
+			if active_effect != -1:
+				player.activate_powerup(active_effect)
+			else:
+				print("No powerup in slot 1 to activate.")
+		
+		# KP Fallback
 		elif ek == KEY_KP_1:
-			player.activate_powerup(0)
-		elif ek == KEY_KP_2:
-			player.activate_powerup(3 if is_sng else 2)
+			var active_effect = -1
+			if player.special_tiles_manager:
+				for effect_key in player.special_tiles_manager.inventory:
+					if player.special_tiles_manager.inventory[effect_key]:
+						active_effect = effect_key
+						break
+			if active_effect != -1:
+				player.activate_powerup(active_effect)
 			
 		# Action Buttons (Remappable)
 		elif ek == SettingsManager.get_control_keycode("attack_mode"):