feat: implement calculator app with pseudo-auth and CI/CD

- Calculator with full keyboard support and click interaction
- Pseudo-auth via localStorage (any login accepted)
- Dark theme (AntD ConfigProvider + custom styles)
- Responsive layout from 320px
- CI/CD: service.yaml + .drone.yml for deployment to test-calculator.vigdorov.ru

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

vite.config.ts

@@ -0,0 +1,16 @@
+import { defineConfig } from 'vite'
+import react from '@vitejs/plugin-react'
+
+export default defineConfig({
+  plugins: [react()],
+  build: {
+    rollupOptions: {
+      output: {
+        manualChunks: {
+          vendor: ['react', 'react-dom', 'react-router-dom'],
+          antd: ['antd', '@ant-design/icons'],
+        },
+      },
+    },
+  },
+})