fix: stable compose project name, drop fixed container_name

Avoids global name conflicts when compose project name differs from
orphaned containers (playgroundschwenkonline vs playground).

Co-authored-by: Cursor <cursoragent@cursor.com>

compose.yml

@@ -1,3 +1,5 @@
+name: playground
+
 services:
 
   playground:
@@ -6,7 +8,6 @@ services:
       - ./public:/usr/share/nginx/html:ro
       - ./nginx/default.conf:/etc/nginx/conf.d/default.conf:ro
       - ./nginx/security-headers.conf:/etc/nginx/conf.d/security-headers.conf:ro
-    container_name: playground
     restart: unless-stopped
     labels:
       - "traefik.enable=true"
@@ -26,7 +27,6 @@ services:
       - WEBHOOK_SECRET=${WEBHOOK_SECRET}
       - DEPLOY_GIT_TOKEN=${DEPLOY_GIT_TOKEN:-}
       - DEPLOY_BRANCH=${DEPLOY_BRANCH:-main}
-    container_name: playground-deploy-hook
     restart: unless-stopped
     labels:
       - "traefik.enable=true"