Fix regex to properly validate HTTP status line format

Changed the regex in CreateResponse to ensure it matches only status lines starting at the beginning of the string. This prevents potential misinterpretation of malformed input and improves overall response handling accuracy.

Author: koriym

src/Http/CreateResponse.php

@@ -71,7 +71,7 @@ private function getCode(string $status): int
             return 500;
         }
 
-        if (preg_match('/HTTP\/\d\.\d\s+(\d{3})/', $status, $match)) {
+        if (preg_match('/^HTTP\/\d\.\d\s+(\d{3})/', $status, $match)) {
             return (int) $match[1];
         }