add key characters to props

scripts/game_key.gd

@@ -105,6 +105,11 @@ func _set_labels() -> void:
 		else ""
 	)
 
+	props.main_char = main_char
+	props.shift_char = shift_char
+	props.alt_char = alt_char
+	props.alt_shift_char = alt_shift_char
+
 	if (
 		props.physical_keycode == KEY_SPACE
 		or (!main_char and !shift_char and !alt_char and !alt_shift_char)

scripts/key_props.gd

@@ -3,6 +3,11 @@ class_name KeyProps
 var physical_keycode: Key
 var location: KeyLocation
 
+var main_char: String
+var shift_char: String
+var alt_char: String
+var alt_shift_char: String
+
 var width_ratio_init: float
 var width_ratio: float