fix: add SIGHUP/SIGTERM handling, modernize PHP support and CI

Signal handling fixes:
- SignalListener: add SIGHUP/SIGTERM handling for both Swoole
  and Workerman drivers in master and worker processes
- Prevent 100% CPU when IDE terminal is closed by ensuring
  graceful shutdown on terminal hangup

PHP version support:
- Widen PHP constraint to 8.3, 8.4, 8.5
- Bump doctrine/dbal from ^2.13.1 to ^4.4
- Bump php-cs-fixer to ^3.64, phpstan to ^1.12
- Bump swoole/ide-helper to ^5.0
- Drop phpunit ^8.5 (EOL), keep ^9.0

CI updates:
- actions/checkout@v3 → @v4 (Node.js 20 deprecated)
- Bump static analysis/code style PHP from 8.1 to 8.3

src/ZM/Process/ProcessStateManager.php

@@ -31,7 +31,7 @@ class ProcessStateManager
      * @throws ZMKnownException
      * @internal
      */
-    public static function removeProcessState(int $type, null|int|string $id_or_name = null): void
+    public static function removeProcessState(int $type, int|string|null $id_or_name = null): void
     {
         switch ($type) {
             case ZM_PROCESS_MASTER: