feat: Setup React Frontend (Issue #1)

- Initialize Vite + React + TypeScript project
- Install dependencies (React Router, Zustand, Axios, Tailwind CSS)
- Configure Tailwind CSS and PostCSS
- Create basic folder structure
- Setup ESLint and Prettier
- Create placeholder pages (Login, Dashboard, Logs, Alerts, etc.)
- Create Layout and ProtectedRoute components
- Add TypeScript types

Closes #1

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

frontend/vite.config.ts

@@ -0,0 +1,21 @@
+import { defineConfig } from 'vite'
+import react from '@vitejs/plugin-react'
+
+// https://vitejs.dev/config/
+export default defineConfig({
+  plugins: [react()],
+  server: {
+    port: 3000,
+    host: true,
+    proxy: {
+      '/api': {
+        target: 'http://localhost:8080',
+        changeOrigin: true,
+      }
+    }
+  },
+  build: {
+    outDir: 'dist',
+    sourcemap: true,
+  }
+})