chore: Remove nginx from docker-compose files

Simplified setup for local network access - access FastAPI directly on port 8000

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

docker-compose.local.yml

@@ -135,20 +135,6 @@ services:
     networks:
       - social-network
 
-  nginx:
-    image: nginx:alpine
-    container_name: social-automation-nginx
-    ports:
-      - "80:80"
-    volumes:
-      - ./nginx/nginx.local.conf:/etc/nginx/nginx.conf:ro
-      - ./dashboard/static:/usr/share/nginx/html/static:ro
-    depends_on:
-      - app
-    restart: unless-stopped
-    networks:
-      - social-network
-
 volumes:
   postgres_data:
   redis_data: