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/components/MessageBubble.jsx

@@ -0,0 +1,39 @@
+export default function MessageBubble({ message, onReplay }) {
+  const isUser = message.role === 'user'
+
+  return (
+    <div className={`flex ${isUser ? 'justify-end' : 'justify-start'} px-4 py-1.5`}>
+      <div className={`flex items-start gap-3 max-w-[80%] ${isUser ? 'flex-row-reverse' : ''}`}>
+        {!isUser && (
+          <div className="w-8 h-8 rounded-full bg-indigo-600/20 flex items-center justify-center shrink-0 mt-0.5">
+            <span className="text-indigo-400 text-sm">AI</span>
+          </div>
+        )}
+        <div>
+          <div
+            className={`rounded-2xl px-4 py-2.5 text-sm leading-relaxed whitespace-pre-wrap ${
+              isUser
+                ? 'bg-indigo-600 text-white'
+                : message.isError
+                  ? 'bg-red-900/40 text-red-200 border border-red-800/50'
+                  : 'bg-gray-800 text-gray-100'
+            }`}
+          >
+            {message.content}
+          </div>
+          {!isUser && !message.isError && onReplay && (
+            <button
+              onClick={() => onReplay(message.content)}
+              className="mt-1 ml-1 text-gray-500 hover:text-indigo-400 transition-colors"
+              title="Replay audio"
+            >
+              <svg className="w-4 h-4" fill="none" viewBox="0 0 24 24" stroke="currentColor" strokeWidth={2}>
+                <path strokeLinecap="round" strokeLinejoin="round" d="M15.536 8.464a5 5 0 010 7.072M17.95 6.05a8 8 0 010 11.9M6.5 9H4a1 1 0 00-1 1v4a1 1 0 001 1h2.5l4 4V5l-4 4z" />
+              </svg>
+            </button>
+          )}
+        </div>
+      </div>
+    </div>
+  )
+}