Move desktop and e2e into examples/ directory

- desktop/ → examples/django-react-desktop-app/
- e2e/ → examples/django-react-site/
- example/ → examples/django-react-site/backend/
- Update Dockerfile.test, Makefile, playwright config, and
  django.config.mjs path references

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

examples/django-react-desktop-app/frontend/vite.config.ts

@@ -0,0 +1,12 @@
+import { defineConfig } from 'vite'
+import react from '@vitejs/plugin-react'
+
+export default defineConfig({
+    plugins: [react()],
+    server: {
+        proxy: {
+            '/api': 'http://127.0.0.1:8765',
+            '/ws': { target: 'ws://127.0.0.1:8765', ws: true },
+        },
+    },
+})