feat: unified HomeAI dashboard — merge character + desktop into single app

Combines homeai-character (service status, character profiles, editor) and
homeai-desktop (chat with voice I/O) into homeai-dashboard on port 5173.

- 4-page sidebar layout: Dashboard, Chat, Characters, Editor
- Merged Vite middleware: health checks, service restart, bridge proxy
- Bridge upgraded to ThreadingHTTPServer (fixes LAN request queuing)
- TTS strips emojis before synthesis
- Updated start.sh with new launchd service names
- Added preload-models to startup sequence

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

homeai-dashboard/src/lib/api.js

@@ -0,0 +1,44 @@
+export async function sendMessage(text) {
+  const res = await fetch('/api/agent/message', {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ message: text, agent: 'main' }),
+  })
+  if (!res.ok) {
+    const err = await res.json().catch(() => ({ error: 'Request failed' }))
+    throw new Error(err.error || `HTTP ${res.status}`)
+  }
+  const data = await res.json()
+  return data.response
+}
+
+export async function synthesize(text, voice) {
+  const res = await fetch('/api/tts', {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ text, voice }),
+  })
+  if (!res.ok) throw new Error('TTS failed')
+  return await res.arrayBuffer()
+}
+
+export async function transcribe(wavBlob) {
+  const res = await fetch('/api/stt', {
+    method: 'POST',
+    headers: { 'Content-Type': 'audio/wav' },
+    body: wavBlob,
+  })
+  if (!res.ok) throw new Error('STT failed')
+  const data = await res.json()
+  return data.text
+}
+
+export async function healthCheck() {
+  try {
+    const res = await fetch('/api/health?url=' + encodeURIComponent('http://localhost:8081/'), { signal: AbortSignal.timeout(5000) })
+    const data = await res.json()
+    return data.status === 'online'
+  } catch {
+    return false
+  }
+}