Updated event_bus to have shield change single; attempted to update

player's set shield but running into problems at runtime.

event_bus.gd

@@ -0,0 +1,7 @@
+extends Node
+
+@warning_ignore_start("unused_signal") # since otherwise Godot will throw a warning that the signal is unused in current scope
+
+signal shield_changed(max_value: int, old_value: int, new_value: int)
+
+@warning_ignore_restore("unused_signal") # put any future signals you add between the two ignore annotations