feat: add homeai-desktop web assistant with LAN access

Adds the desktop web assistant app (Vite + React) with OpenClaw bridge
proxy and exposes it on the local network (host: 0.0.0.0, port 5174).

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

homeai-desktop/src/hooks/useBridgeHealth.js

@@ -0,0 +1,18 @@
+import { useState, useEffect, useRef } from 'react'
+import { healthCheck } from '../lib/api'
+
+export function useBridgeHealth() {
+  const [isOnline, setIsOnline] = useState(null)
+  const intervalRef = useRef(null)
+
+  useEffect(() => {
+    const check = async () => {
+      setIsOnline(await healthCheck())
+    }
+    check()
+    intervalRef.current = setInterval(check, 15000)
+    return () => clearInterval(intervalRef.current)
+  }, [])
+
+  return isOnline
+}