refactor(infra) : align prod setup with Lesstime pattern

Single container with supervisord (Nginx + PHP-FPM), 3-stage
Dockerfile build, pre-built image from registry, port 8086.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

infra/prod/docker-compose.prod.yml

@@ -1,42 +1,12 @@
 services:
-  php:
-    container_name: php-coltura-fpm
-    build:
-      context: ../../
-      dockerfile: infra/prod/Dockerfile
-      target: php-base
-    environment:
-      APP_ENV: prod
-      APP_DEBUG: 0
-      DATABASE_URL: "postgresql://${POSTGRES_USER}:${POSTGRES_PASSWORD}@db:5432/${POSTGRES_DB}?serverVersion=16&charset=utf8"
-    volumes:
-      - uploads_data:/var/www/html/var/uploads
-    depends_on:
-      - db
-    restart: unless-stopped
-
-  nginx:
-    container_name: nginx-coltura
-    build:
-      context: ../../
-      dockerfile: infra/prod/Dockerfile
-      target: nginx
-    depends_on:
-      - php
+  app:
+    image: gitea.malio.fr/malio-dev/coltura:${COLTURA_IMAGE_TAG:-latest}
+    container_name: coltura-app
+    env_file: .env
     ports:
       - "8086:80"
-    restart: unless-stopped
-
-  db:
-    image: postgres:16-alpine
-    environment:
-      POSTGRES_DB: ${POSTGRES_DB}
-      POSTGRES_USER: ${POSTGRES_USER}
-      POSTGRES_PASSWORD: ${POSTGRES_PASSWORD}
     volumes:
-      - pg_data:/var/lib/postgresql/data
+      - ./config/jwt:/var/www/html/config/jwt:ro
+    extra_hosts:
+      - "host.docker.internal:host-gateway"
     restart: unless-stopped
-
-volumes:
-  pg_data:
-  uploads_data: