feat(container): support comma-separated roles

Allow s6 services to start for specific roles like horizon,
scheduler, nightwatch, and flux while keeping all as the default.

.env.development.example

@@ -7,6 +7,7 @@ APP_URL=http://localhost
 APP_PORT=8000
 APP_DEBUG=true
 SSH_MUX_ENABLED=true
+COOLIFY_CONTAINER_ROLE=all
 
 # PostgreSQL Database Configuration
 DB_DATABASE=coolify