feat: add Monaco editor, API error handling, and CI/CD

- Monaco Editor: script editor with syntax highlighting
- API: error handling with ApiError class and token management
- CI/CD: Gitea Actions workflow for build, Docker, and deploy
- Docker: multi-stage build with nginx
- nginx.conf: SPA fallback and API proxy

nginx.conf

@@ -0,0 +1,32 @@
+server {
+    listen 80;
+    server_name localhost;
+    root /usr/share/nginx/html;
+    index index.html;
+
+    # Gzip
+    gzip on;
+    gzip_types text/plain text/css application/json application/javascript text/xml application/xml text/javascript;
+    gzip_min_length 1000;
+
+    # SPA fallback
+    location / {
+        try_files $uri $uri/ /index.html;
+    }
+
+    # API proxy
+    location /api/ {
+        proxy_pass http://backend:8080;
+        proxy_http_version 1.1;
+        proxy_set_header Upgrade $http_upgrade;
+        proxy_set_header Connection "upgrade";
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+    }
+
+    # Cache static assets
+    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2)$ {
+        expires 1y;
+        add_header Cache-Control "public, immutable";
+    }
+}