fix(docker): always pull the latest PHP 8.4 base image on release builds

Picks up PHP 8.4.27 for CVE-2026-109618 and CVE-2026-109619 (critical RCE)
via the floating 1-php8.4-alpine tag.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

CHANGELOG.md

@@ -19,6 +19,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   - `phpstan/phpstan` 2.2.5 → 2.2.16
 - Docker builds copy `symfony.lock` so Flex doesn't re-apply recipes during `composer install`
 
+### Fixed
+
+- Renovate no longer pins `symfony/monolog-bundle` to `~7.4` — it is versioned independently (4.x) and was blocked from updates (#39)
+
+### Security
+
+- Release images are built against the latest picks up PHP 8.4.27 for CVE-2026-109618 and CVE-2026-109619 (critical RCE)
+
 ## [0.2.1] - 2026-07-31
 
 ### Added