Allows opening a device via the synchronous API on a caller-chosen thread
and then handing it to the async wrapper. This matters on macOS, where
hidapi's IOHIDManager is bound to the run loop of the thread that created
the HidApi: enumerate/open must happen on that thread, but
AsyncStreamDeck::connect runs them via block_in_place on whatever tokio
worker is current, which can crash (EXC_BREAKPOINT in CoreFoundation)
when the device set changes, e.g. after sleep/wake.
With this, an application can own the HidApi on a dedicated thread, open
devices there with StreamDeck::connect, and still use the async API for
everything else.
