fix: accept int|string natively in Sequence validator without casting

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: abnegate

src/Database/Validator/Sequence.php

@@ -41,11 +41,7 @@ public function isValid($value): bool
             return false;
         }
 
-        if (\is_int($value)) {
-            $value = (string) $value;
-        }
-
-        if (!\is_string($value)) {
+        if (!\is_string($value) && !\is_int($value)) {
             return false;
         }