Fixes#7487.
`KMN_API` defines only import/export/static modifiers for functions, so
it makes no sense to apply it to a typedef. (Previously, I thought it
also included a calling convention, but it doesn't.)
Adds infrastructure required to support caps lock control on keyboard
activation per #5822.
Keyboardprocessor implementation is currently a stub, and engines will
need corresponding updates to support the new API.
- uint16_t
- defined km_kbp_event_flags to define the bitfield
- bitfield has value KM_KBP_EVENT_FLAG_TOUCH for touch events
- ignored everywhere, currently