Add cLuaWindow OnClicked Callback (#3901)

Server/Plugins/APIDump/Hooks/OnPlayerOpeningWindow.lua

@@ -0,0 +1,20 @@
+return
+{
+	HOOK_PLAYER_OPENING_WINDOW =
+	{
+		CalledWhen = "Called when a player is about to open a window",
+		DefaultFnName = "OnPlayerOpeningWindow",  -- also used as pagename
+		Desc = [[
+			This hook is called when a player is about to open a window, e.g. when they click on a chest or a furnace.
+		]],
+		Params =
+		{
+			{ Name = "Player", Type = "{{cPlayer}}", Notes = "The player who is opening the window" },
+			{ Name = "Window", Type = "{{cWindow}}", Notes = "The window that is being opened" },
+		},
+		Returns = [[
+			If the function returns false or no value, the next plugin's callback is called, and finally
+			Cuberite will process the opening window. If the function returns true, no other callback is called for this event.
+		]],
+	},  -- HOOK_PLAYER_OPENING_WINDOW
+}