commands: document <criteria> focus

sway/sway.5.scd

@@ -84,6 +84,9 @@ They are expected to be used with *bindsym* or at runtime through *swaymsg*(1).
 *floating* enable|disable|toggle
 	Make focused view floating, non-floating, or the opposite of what it is now.
 
+<criteria> *focus*
+	Moves focus to the container that matches the specified criteria.
+
 *focus* up|right|down|left
 	Moves focus to the next container in the specified direction.