Add joystick button index boundary check. Increase max. button number to 128 (max. buttons supported by DirectInput).

(cherry picked from commit 61ea8f83377952a8ca8e1cb5cf8ec1099ca8369f)

core/os/input_event.h

@@ -85,7 +85,7 @@ enum JoystickList {
 	JOY_BUTTON_20 = 20,
 	JOY_BUTTON_21 = 21,
 	JOY_BUTTON_22 = 22,
-	JOY_BUTTON_MAX = 23,
+	JOY_BUTTON_MAX = 128, // Android supports up to 36 buttons. DirectInput supports up to 128 buttons.
 
 	JOY_L = JOY_BUTTON_4,
 	JOY_R = JOY_BUTTON_5,

doc/classes/@GlobalScope.xml

@@ -1015,8 +1015,11 @@
 		<constant name="JOY_BUTTON_22" value="22" enum="JoystickList">
 			Gamepad button 22.
 		</constant>
-		<constant name="JOY_BUTTON_MAX" value="23" enum="JoystickList">
-			Represents the maximum number of joystick buttons supported.
+		<constant name="JOY_BUTTON_MAX" value="128" enum="JoystickList">
+			The maximum number of game controller buttons supported by the engine. The actual limit may be lower on specific platforms:
+			- Android: Up to 36 buttons.
+			- Linux: Up to 80 buttons.
+			- Windows and macOS: Up to 128 buttons.
 		</constant>
 		<constant name="JOY_SONY_CIRCLE" value="1" enum="JoystickList">
 			DualShock circle button.

main/input_default.cpp

@@ -775,7 +775,8 @@ InputDefault::InputDefault() {
 void InputDefault::joy_button(int p_device, int p_button, bool p_pressed) {
 	_THREAD_SAFE_METHOD_;
 	Joypad &joy = joy_names[p_device];
-	//printf("got button %i, mapping is %i\n", p_button, joy.mapping);
+	ERR_FAIL_INDEX(p_button, JOY_BUTTON_MAX);
+
 	if (joy.last_buttons[p_button] == p_pressed) {
 		return;
 	}