Add example to enable three-finger drag in input configuration (#3798)

* Add example to enable three-finger drag

* Clarify comment

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Co-authored-by: David Heinemeier Hansson <david@hey.com>

config/hypr/input.conf

@@ -24,6 +24,9 @@ input {
 
     # Control the speed of your scrolling
     scroll_factor = 0.4
+
+    # Move windows with three-finger drag
+    # drag_3fg = 1
   }
 }