Bump PHP, Nginx and MariaDB versions

Update container base images used by the project:
- docker/compose.yml:
nginx from 1.27-alpine -> 1.31-alpine,
mariadb from 11.4 -> 11.8 (still overridable via DOOGLE_* env vars)
- docker/php/Dockerfile: php from 8.3-fpm -> 8.4-fpm
- set GitHub Actions PHP to 8.4

These bumps bring newer upstream releases (security/feature updates). Validate compatibility with PHP 8.4 and MariaDB 11.8 in CI or local testing.

Author: safesploit

.github/workflows/ci.yml

@@ -25,7 +25,7 @@ jobs:
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
         with:
-          php-version: '8.3'
+          php-version: '8.4'
           extensions: dom, pdo, pdo_sqlite
           coverage: none
 

docker/compose.yml

@@ -2,7 +2,7 @@ name: ${DOOGLE_COMPOSE_PROJECT:-doogle}
 
 services:
   web:
-    image: ${DOOGLE_NGINX_IMAGE:-nginx:1.27-alpine}
+    image: ${DOOGLE_NGINX_IMAGE:-nginx:1.31-alpine}
     depends_on:
       app:
         condition: service_started
@@ -54,7 +54,7 @@ services:
       - composer_vendor:/var/www/html/vendor
 
   mysql_db:
-    image: ${DOOGLE_MARIADB_IMAGE:-mariadb:11.4}
+    image: ${DOOGLE_MARIADB_IMAGE:-mariadb:11.8}
     environment:
       MARIADB_DATABASE: "${DB_DATABASE:-doogle}"
       MARIADB_USER: "${DB_USERNAME:-doogle}"

docker/php/Dockerfile

@@ -1,4 +1,4 @@
-FROM php:8.3-fpm
+FROM php:8.4-fpm
 
 RUN apt-get update \
     && apt-get install -y --no-install-recommends \