Add React frontend and Django backend code

- React components: Dashboard, MemoryCalendar, SearchBox, ToolList
- Django backend structure
- Package configuration files

code/frontend/package.json

@@ -0,0 +1,30 @@
+{
+  "name": "lobster-monitor-frontend",
+  "version": "1.0.0",
+  "description": "龙虾舰队监控中心 - React 前端",
+  "private": true,
+  "dependencies": {
+    "react": "^18.2.0",
+    "react-dom": "^18.2.0",
+    "react-scripts": "5.0.1",
+    "axios": "^1.6.0"
+  },
+  "scripts": {
+    "start": "react-scripts start",
+    "build": "react-scripts build",
+    "test": "react-scripts test",
+    "eject": "react-scripts eject"
+  },
+  "browserslist": {
+    "production": [
+      ">0.2%",
+      "not dead",
+      "not op_mini all"
+    ],
+    "development": [
+      "last 1 chrome version",
+      "last 1 firefox version",
+      "last 1 safari version"
+    ]
+  }
+}