Update docker-compose.yml with all environment variables and PostgreSQL

Major changes:
- Switch from MariaDB to PostgreSQL 16
- Add all required environment variables to web service:
  - SECRET_KEY, DEBUG, ALLOWED_HOSTS
  - CSRF_TRUSTED_ORIGINS, CORS_ALLOWED_ORIGINS
  - Email configuration (HOST, PORT, USER, PASSWORD, TLS)
  - Gunicorn settings (WORKERS, TIMEOUT)
- Add SECRET_KEY to celery services (required for Django)
- Update all services to depend on 'postgres' instead of 'mariadb'
- Update DATABASE_URL to use PostgreSQL format
- Update .env.docker.example to reflect PostgreSQL and add WEB_PORT

All environment variables now properly declared in compose file
with ${VAR} syntax for Portainer/Docker compatibility.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

docker-compose.yml

@@ -2,25 +2,22 @@ version: '3.8'
 
 services:
   # =================================================================
-  # MariaDB Database Service
+  # PostgreSQL Database Service
   # =================================================================
-  mariadb:
-    image: mariadb:11.2
+  postgres:
+    image: postgres:16-alpine
     container_name: keepitgoing-db
     restart: unless-stopped
     environment:
-      MYSQL_DATABASE: ${DB_NAME:-keepitgoing}
-      MYSQL_USER: ${DB_USER:-keepitgoing}
-      MYSQL_PASSWORD: ${DB_PASSWORD}
-      MYSQL_ROOT_PASSWORD: ${DB_ROOT_PASSWORD}
-      MYSQL_CHARACTER_SET_SERVER: utf8mb4
-      MYSQL_COLLATION_SERVER: utf8mb4_unicode_ci
+      POSTGRES_DB: ${DB_NAME:-keepitgoing}
+      POSTGRES_USER: ${DB_USER:-keepitgoing}
+      POSTGRES_PASSWORD: ${DB_PASSWORD}
     volumes:
-      - db_data:/var/lib/mysql
+      - db_data:/var/lib/postgresql/data
     networks:
       - backend
     healthcheck:
-      test: ["CMD", "healthcheck.sh", "--connect", "--innodb_initialized"]
+      test: ["CMD-SHELL", "pg_isready -U ${DB_USER:-keepitgoing}"]
       interval: 10s
       timeout: 5s
       retries: 5
@@ -54,9 +51,33 @@ services:
     container_name: keepitgoing-web
     restart: unless-stopped
     environment:
+      # Django Settings
       DJANGO_SETTINGS_MODULE: config.settings.selfhosted
-      DATABASE_URL: mysql://${DB_USER:-keepitgoing}:${DB_PASSWORD}@mariadb:3306/${DB_NAME:-keepitgoing}
+      SECRET_KEY: ${SECRET_KEY}
+      DEBUG: ${DEBUG:-False}
+      ALLOWED_HOSTS: ${ALLOWED_HOSTS:-localhost}
+
+      # Security
+      CSRF_TRUSTED_ORIGINS: ${CSRF_TRUSTED_ORIGINS:-http://localhost:8000}
+      CORS_ALLOWED_ORIGINS: ${CORS_ALLOWED_ORIGINS:-http://localhost:8000}
+
+      # Database
+      DATABASE_URL: postgresql://${DB_USER:-keepitgoing}:${DB_PASSWORD}@postgres:5432/${DB_NAME:-keepitgoing}
+
+      # Redis/Celery
       REDIS_URL: redis://redis:6379/0
+
+      # Email
+      EMAIL_HOST: ${EMAIL_HOST:-}
+      EMAIL_PORT: ${EMAIL_PORT:-587}
+      EMAIL_HOST_USER: ${EMAIL_HOST_USER:-}
+      EMAIL_HOST_PASSWORD: ${EMAIL_HOST_PASSWORD:-}
+      EMAIL_USE_TLS: ${EMAIL_USE_TLS:-True}
+      DEFAULT_FROM_EMAIL: ${DEFAULT_FROM_EMAIL:-noreply@localhost}
+
+      # Gunicorn
+      GUNICORN_WORKERS: ${GUNICORN_WORKERS:-3}
+      GUNICORN_TIMEOUT: ${GUNICORN_TIMEOUT:-60}
     volumes:
       - ./media:/app/media
       - static_files:/app/staticfiles
@@ -66,7 +87,7 @@ services:
       - frontend
       - backend
     depends_on:
-      mariadb:
+      postgres:
         condition: service_healthy
       redis:
         condition: service_healthy
@@ -88,12 +109,13 @@ services:
     restart: unless-stopped
     environment:
       DJANGO_SETTINGS_MODULE: config.settings.selfhosted
-      DATABASE_URL: mysql://${DB_USER:-keepitgoing}:${DB_PASSWORD}@mariadb:3306/${DB_NAME:-keepitgoing}
+      SECRET_KEY: ${SECRET_KEY}
+      DATABASE_URL: postgresql://${DB_USER:-keepitgoing}:${DB_PASSWORD}@postgres:5432/${DB_NAME:-keepitgoing}
       REDIS_URL: redis://redis:6379/0
     networks:
       - backend
     depends_on:
-      mariadb:
+      postgres:
         condition: service_healthy
       redis:
         condition: service_healthy
@@ -110,12 +132,13 @@ services:
     restart: unless-stopped
     environment:
       DJANGO_SETTINGS_MODULE: config.settings.selfhosted
-      DATABASE_URL: mysql://${DB_USER:-keepitgoing}:${DB_PASSWORD}@mariadb:3306/${DB_NAME:-keepitgoing}
+      SECRET_KEY: ${SECRET_KEY}
+      DATABASE_URL: postgresql://${DB_USER:-keepitgoing}:${DB_PASSWORD}@postgres:5432/${DB_NAME:-keepitgoing}
       REDIS_URL: redis://redis:6379/0
     networks:
       - backend
     depends_on:
-      mariadb:
+      postgres:
         condition: service_healthy
       redis:
         condition: service_healthy