refactor: remove source host allowlist from direct login

exec/lib/Settings.php

@@ -64,7 +64,6 @@ final class Settings
             'MAIL_LOGIN_REDIRECT_URL' => '/',
             'LOGIN_KEY_TTL' => '30',
             'USER_IP_BOUND' => '1',
-            'MAIL_LOGIN_ALLOWED_SOURCE_HOSTS' => 's1.abc.pl,serwer.mojserwer.pl,serwer2.xxb.ovh',
             'MAIL_LOGIN_SOURCE_SERVER_NAME' => '',
             'MAIL_LOGIN_CLIENT_IP_MODE' => 'direct',
             'MAIL_LOGIN_TRUSTED_PROXIES' => '',
@@ -136,14 +135,6 @@ final class Settings
         return $this->getString('USER_IP_BOUND', '1') === '1';
     }
 
-    /**
-     * @return list<string>
-     */
-    public function allowedSourceHosts(): array
-    {
-        return $this->csvHosts('MAIL_LOGIN_ALLOWED_SOURCE_HOSTS');
-    }
-
     public function sourceServerName(): string
     {
         return $this->sanitizeServerName($this->getString('MAIL_LOGIN_SOURCE_SERVER_NAME', ''));
@@ -213,25 +204,6 @@ final class Settings
         return substr($name, 0, 32);
     }
 
-    /**
-     * @return list<string>
-     */
-    private function csvHosts(string $key): array
-    {
-        $raw = $this->getString($key, '');
-        if ($raw === '') {
-            return [];
-        }
-        $out = [];
-        foreach (explode(',', $raw) as $item) {
-            $host = self::normalizeHost($item);
-            if ($host !== '') {
-                $out[] = $host;
-            }
-        }
-        return array_values(array_unique($out));
-    }
-
     /**
      * @return list<string>
      */