pcre: various minor refactorings (2026-09 N1)

[Girgias]

No description provided.

[devnexen]

this is the only change that concerns me a bit. would it be possible to try at least locally this change (with ASAN) ?

❯ can you draft a test to trigger this issue ?zm_globals_dtor_pcre → zend_hash_destroy(&char_tables)).

--TEST--
preg_match(): locale-keyed char tables cache must not borrow a request-lifetime key
--SKIPIF--
<?php
if (setlocale(LC_CTYPE, 'C.UTF-8', 'en_US.UTF-8', 'en_US.utf8', 'de_DE.UTF-8', 'de_DE.utf8') === false) {
    die('skip no suitable non-C locale available');
}
?>
--FILE--
<?php
var_dump(setlocale(LC_CTYPE, 'C.UTF-8', 'en_US.UTF-8', 'en_US.utf8', 'de_DE.UTF-8', 'de_DE.utf8') !== false);
setlocale(LC_CTYPE, setlocale(LC_CTYPE, 0));
var_dump(preg_match('/[[:alpha:]]/', 'a'));
?>
--EXPECT--
bool(true)
int(1)