Audit Input

Sweep for Enhanced Input faults that produce no error anywhere: an action no context maps, which binds fine and never fires; rows with no action or no key, drawn exactly like working ones; an Axis2D action where every digital key drives the first axis because nothing carries a Swizzle, which is half a movement scheme silently dead; and, on UE 5.7 and later, mappings stranded in the deprecated array that the engine no longer reads.