feat: Add powerup inventory UI and mobile touch controls including a virtual joystick and action buttons.

scripts/managers/touch_controls.gd

@@ -138,6 +138,8 @@ func _find_or_create_action_button(container: Control, button_name: String, icon
 			
 			btn.button_down.connect(func(): _on_button_pressed(button_name))
 			btn.button_up.connect(func(): _on_button_released(button_name))
+			
+		_ensure_shortcut_label(btn, button_name)
 		return btn
 		
 	# Create new
@@ -164,7 +166,9 @@ func _create_action_button(button_name: String, icon: String, pos: Vector2) -> B
 	btn.button_down.connect(func(): _on_button_pressed(button_name))
 	btn.button_up.connect(func(): _on_button_released(button_name))
 	
-	_style_button(btn, button_opacity)
+	# Helper to ensure label exists
+	_ensure_shortcut_label(btn, button_name)
+			
 	return btn
 
 func _style_button(btn: Button, opacity: float):
@@ -194,6 +198,29 @@ func _style_button(btn: Button, opacity: float):
 	# Prevent buttons from stealing focus (fixes Spacebar activation)
 	btn.focus_mode = Control.FOCUS_NONE
 
+func _ensure_shortcut_label(btn: Button, button_name: String):
+	if btn.has_node("ShortcutLabel"):
+		return
+		
+	# Add Keyboard Shortcut Label
+	var shortcut_lbl = Label.new()
+	shortcut_lbl.name = "ShortcutLabel"
+	shortcut_lbl.set_anchors_preset(Control.PRESET_FULL_RECT)
+	shortcut_lbl.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
+	shortcut_lbl.vertical_alignment = VERTICAL_ALIGNMENT_BOTTOM
+	shortcut_lbl.offset_bottom = 20 # Below button
+	shortcut_lbl.add_theme_font_size_override("font_size", 16)
+	shortcut_lbl.add_theme_color_override("font_outline_color", Color.BLACK)
+	shortcut_lbl.add_theme_constant_override("outline_size", 4)
+	
+	match button_name:
+		"Grab": shortcut_lbl.text = "Space"
+		"Put": shortcut_lbl.text = "R"
+		"Special": shortcut_lbl.text = "C"
+		"SpawnBoost": shortcut_lbl.text = "V"
+		
+	btn.add_child(shortcut_lbl)
+
 func _on_joystick_direction(direction: Vector2i):
 	if local_player and local_player.has_method("simple_move_to"):
 		var target_pos = local_player.current_position + direction