Implement responsiveness event
This MR implements the responsiveness event discussed by wlr-protocols!127.
The foreign-toplevel executable listens for responsiveness event from the server and prints them whenever a toplevel goes unresponsive.
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This MR implements the responsiveness event discussed by wlr-protocols!127.
The foreign-toplevel executable listens for responsiveness event from the server and prints them whenever a toplevel goes unresponsive.