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/Dockerfile

@@ -0,0 +1,11 @@
+FROM node:20-alpine AS build
+WORKDIR /app
+COPY package*.json ./
+RUN npm install
+COPY . .
+RUN npm run build
+
+FROM nginx:alpine
+COPY --from=build /app/dist /usr/share/nginx/html
+COPY nginx.conf /etc/nginx/conf.d/default.conf
+EXPOSE 80