fix: detect imported Symfony cookie calls

[Jonas Elfering (keulinho)]

Summary

Restore detection of insecure Symfony Cookie construction and factory calls that use an imported Cookie class.

Details

• use PHPStan's inferred expression type to identify Symfony Cookie instances
• retain the existing handling for named arguments and fluent withSecure calls
• make the existing cookie-rule test pass with all ten intended violations

Validation

• vendor/bin/phpunit tests/Rule/ForbidInsecureSymfonyCookieRuleTest.php
• php -d memory_limit=1G vendor/bin/phpunit
• php -d memory_limit=1G vendor/bin/phpstan analyse src/Rule/ForbidInsecureSymfonyCookieRule.php --no-progress
• PHP_CS_FIXER_IGNORE_ENV=1 vendor/bin/php-cs-fixer fix --dry-run --diff