[php-src] Issue #13307: Constant as default value

Issue: https://github.com/php/php-src/issues/13307 Author: SVGAnimate ### Description The following code: ```php <?php function foo(int $p="1.1") {} ``` Resulted in this output: ``` Fatal error: Cannot use string as default value for parameter $p of type int ``` But not the following code: ```php <?php const default_value = "string"; function foo(int $p=default_value) {} ``` From there follows a series of different behaviors <hr /> The following code: ```php <?php define('undefined', false);// or true : Bool function foo(int $p=undefined) { var_dump($p); } foo(1); foo(); ``` Resulted in this output: ``` int(1) int(0) ``` <hr/> The following code: ```php <?php define('undefined', 0.1);// Float function foo(int $p=undefined) { var_dump($p); } foo(1); foo(); ``` Resulted in this output: ``` int(1) Deprecated: Implicit conversion from float 0.1 to int loses precision in /tmp/preview on line 4 int(0) ``` ### PHP Version PHP 8.3.2 ### Operating System Ubuntu 24.04