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/hooks/useTtsPlayback.js

@@ -0,0 +1,56 @@
+import { useState, useRef, useCallback } from 'react'
+import { synthesize } from '../lib/api'
+
+export function useTtsPlayback(voice) {
+  const [isPlaying, setIsPlaying] = useState(false)
+  const audioCtxRef = useRef(null)
+  const sourceRef = useRef(null)
+
+  const getAudioContext = () => {
+    if (!audioCtxRef.current || audioCtxRef.current.state === 'closed') {
+      audioCtxRef.current = new AudioContext()
+    }
+    return audioCtxRef.current
+  }
+
+  const speak = useCallback(async (text) => {
+    if (!text) return
+
+    // Stop any current playback
+    if (sourceRef.current) {
+      try { sourceRef.current.stop() } catch {}
+    }
+
+    setIsPlaying(true)
+    try {
+      const audioData = await synthesize(text, voice)
+      const ctx = getAudioContext()
+      if (ctx.state === 'suspended') await ctx.resume()
+
+      const audioBuffer = await ctx.decodeAudioData(audioData)
+      const source = ctx.createBufferSource()
+      source.buffer = audioBuffer
+      source.connect(ctx.destination)
+      sourceRef.current = source
+
+      source.onended = () => {
+        setIsPlaying(false)
+        sourceRef.current = null
+      }
+      source.start()
+    } catch (err) {
+      console.error('TTS playback error:', err)
+      setIsPlaying(false)
+    }
+  }, [voice])
+
+  const stop = useCallback(() => {
+    if (sourceRef.current) {
+      try { sourceRef.current.stop() } catch {}
+      sourceRef.current = null
+    }
+    setIsPlaying(false)
+  }, [])
+
+  return { isPlaying, speak, stop }
+}