feat: add VPS Monitor backend and frontend services

- Create systemd service for VPS Monitor agent.
- Add FastAPI backend with endpoints for managing VPS configurations and statuses.
- Implement Dockerfile for backend service with required dependencies.
- Create frontend using React with Vite and Tailwind CSS for styling.
- Add API client for communicating with the backend.
- Implement components for displaying VPS information and logs.
- Set up Docker Compose for orchestrating backend and frontend services.
- Add environment configuration files for backend and agent.
- Implement CORS support in the backend for frontend communication.

vps-monitor/frontend/nginx.conf

@@ -0,0 +1,17 @@
+server {
+    listen 80;
+    root /usr/share/nginx/html;
+    index index.html;
+
+    # Proxy vers le backend FastAPI
+    location /api/ {
+        proxy_pass         http://backend:8000;
+        proxy_set_header   Host $host;
+        proxy_set_header   X-Real-IP $remote_addr;
+    }
+
+    # SPA fallback
+    location / {
+        try_files $uri $uri/ /index.html;
+    }
+}