Add support for uosc menu search

[christoph-heinrich]

Already works pretty well for being so simple.
Even works with #13.

A search_debounce of 0 probably doesn't make sense when deletion checking is turned on, but without it's fast enough for that.

Is the script message name fine or do you have an idea for something more general?

[christoph-heinrich]

Please explain why 7c76413 was necessary, because I've noticed that while searching, when I'm typing too fast it doesn't always search for the whole string.
At first I though that the events don't arrive in the correct order, but after checking the mpv code and debugging this it turns out to be the fault of event_loop_exhausted.

I've tried never setting event_loop_exhausted=true and it seems to work fine and search events don't get dropped anymore.

Is it the race condition you described in #13 (comment)?

[po5]

Yeah we must know the real menu state and avoid issues like someone repeatedly activating the "next page" item while we're trying to fetch stuff. This ensures that when there are queued up events we only process the first one.
I guess search could be made to bypass this check, or it could be debounced.

[christoph-heinrich]

memo-next/memo-prev are the only ones where ignoring events makes sense imo.
I'll implement your suggestions from tomasklaen/uosc#587 (comment) so that this restriction can lifted from other events.

[po5]

God that's clean! Thank you.