Refactor API functions to improve parameter aliasing and enhance documentation clarity

api/IsMouseButtonDown.lua

@@ -1,12 +1,14 @@
 ---@diagnostic disable: missing-return, lowercase-global
 ---@meta
 
----@param button 5 or Button5 
----@param 1 or LeftButton  
----@param 2 or RightButton  
----@param 3 or MiddleButton  
----@param 4 or Button4  
----@param 5 or Button5  
----@return 1nil isDown 
+---@alias mouseButton
+---| 1 or "LeftButton" - Primary mouse button
+---| 2 or "RightButton" - Secondary mouse button
+---| 3 or "MiddleButton" - Third mouse button (or clickable scroll control)
+---| 4 or "Button4" - Fourth mouse button
+---| 5 or "Button5" - Fifth mouse button
+
+---@param button mouseButton
+---@return boolean isDown
 ---Returns whether a given mouse button is held down. If no button is specified, returns 1 if any mouse button is held down.
-function IsMouseButtonDown(button, 1 or LeftButton, 2 or RightButton, 3 or MiddleButton, 4 or Button4, 5 or Button5) end
+function IsMouseButtonDown(button) end