feat: add layout components and pages for NxMesh Admin

- Implemented Header, Sidebar, and Layout components for consistent UI structure.
- Created pages for Agents, Certificates, Configurations, Dashboard, and Settings.
- Integrated React Query for data fetching in Agents, Certificates, Configurations, and Dashboard pages.
- Added Tailwind CSS for styling and responsive design.
- Established a utility function for conditional class names.
- Set up Vite configuration for React project with TypeScript support.
- Included global styles and Tailwind CSS configuration.

frontend/tsconfig.json

@@ -0,0 +1,25 @@
+{
+  "compilerOptions": {
+    "target": "ES2020",
+    "useDefineForClassFields": true,
+    "lib": ["ES2020", "DOM", "DOM.Iterable"],
+    "module": "ESNext",
+    "skipLibCheck": true,
+    "moduleResolution": "bundler",
+    "allowImportingTsExtensions": true,
+    "resolveJsonModule": true,
+    "isolatedModules": true,
+    "noEmit": true,
+    "jsx": "react-jsx",
+    "strict": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "noFallthroughCasesInSwitch": true,
+    "baseUrl": ".",
+    "paths": {
+      "@/*": ["src/*"]
+    }
+  },
+  "include": ["src"],
+  "references": [{ "path": "./tsconfig.node.json" }]
+}