Initial implementation of NetWatch network latency monitor

SPA for real-time latency monitoring to 10 internet hosts:
- 250ms update interval with 300s history sparkline graphs
- Color-coded latency display (green <50ms to red >500ms)
- HEAD request timing with no-cors mode for cross-origin support
- Built with Vite + Tailwind CSS v4, all dependencies bundled
- Designed for static bucket deployment

vite.config.js

@@ -0,0 +1,11 @@
+import { defineConfig } from 'vite'
+import tailwindcss from '@tailwindcss/vite'
+
+export default defineConfig({
+  plugins: [tailwindcss()],
+  build: {
+    target: 'esnext',
+    minify: 'esbuild',
+    cssMinify: true,
+  },
+})