Bump PHP_DS_VERSION to 1.8.0

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

Author: rudi-augment

php_ds.h

@@ -20,7 +20,7 @@ extern zend_module_entry ds_module_entry;
 #define phpext_ds_ptr &ds_module_entry
 
 /* Replace with version number for your extension */
-#define PHP_DS_VERSION "1.6.0"
+#define PHP_DS_VERSION "1.8.0"
 
 #ifdef PHP_WIN32
 #  define PHP_API __declspec(dllexport)