Move Playwright, Docker, and package.json into examples/django-react-site

Root directory now contains only the two core packages (django/, react/),
examples/, and top-level docs. All e2e/integration test infrastructure
lives in examples/django-react-site/.

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

examples/django-react-site/docker-compose.test.yml

@@ -0,0 +1,17 @@
+services:
+  redis:
+    image: redis:7-alpine
+    ports:
+      - "6379:6379"
+
+  django:
+    build:
+      context: ../..
+      dockerfile: examples/django-react-site/Dockerfile.test
+    ports:
+      - "8000:8000"
+    depends_on:
+      - redis
+    environment:
+      - REDIS_URL=redis://redis:6379/0
+      - DJANGO_SETTINGS_MODULE=testapp.settings