[php-src] PR #23512: Add array_str_contains() function to standard library

Pull Request: https://github.com/php/php-src/pull/23512 Author: sepehrphpr ### Summary This PR introduces the array_str_contains(array $haystack, string $needle): array function to the standard library for PHP 8.7. ### Motivation Filtering arrays based on substring matching is a very common task in PHP applications. Currently, developers often use: ```php array_filter($array, fn($item) => is_string($item) && str_contains($item, $needle)); Providing a dedicated internal implementation in C brings significant performance improvements, reduces userland boilerplate, and offers an intuitive API consistent with str_contains(). Behavior & Details Filtering & Key Preservation: Returns an array containing only the elements that contain $needle, preserving their original keys (both numeric and string keys). Type Handling: Safely ignores non-string values within the array without throwing notices/warnings. Empty Needle: If $needle is an empty string "", it matches all string elements (consistent with str_contains()). Binary & UTF-8 Safe: Built on top of php_memnstr(), ensuring fast and safe matching for UTF-8 / multi-byte characters and binary strings. Memory & Refcount Safe: Properly handles zval dereferencing and reference counting without leaks. Tests Added comprehensive test suite covering basic matching, numeric/string key preservation, non-string filtering, empty needle, and UTF-8 multi-byte strings in ext/standard/tests/array/array_str_contains..phpt