Mouse button clicks should break latches

[Jules-Bertholet]

#569 contains many fixes to latching behavior to make it more usable and remove various annoyances. However, one major QoL issue remains: several modifiers (especially Shift and Control) are commonly used by applications to change the behavior of mouse buttons, but pressing or releasing these buttons does not break the latch. Therefore, when sticky keys are enabled, after latching a modifier to affect the behavior of the next button press, one must remember to return to the keyboard to unlatch it. Ideally, clicking a mouse button would automatically unlatch all modifiers.

This would presumably require API and compositor changes to implement.

[wismill]

libxkbcommon does not handle mouse events.

This would presumably require API and compositor changes to implement.

#521 should be enough.