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/index.css

@@ -0,0 +1,35 @@
+@import "tailwindcss";
+
+body {
+  margin: 0;
+  background-color: #030712;
+  color: #f3f4f6;
+  -webkit-font-smoothing: antialiased;
+  -moz-osx-font-smoothing: grayscale;
+}
+
+#root {
+  min-height: 100vh;
+}
+
+/* Scrollbar styling for dark theme */
+::-webkit-scrollbar {
+  width: 8px;
+}
+
+::-webkit-scrollbar-track {
+  background: #0a0a0f;
+}
+
+::-webkit-scrollbar-thumb {
+  background: #374151;
+  border-radius: 4px;
+}
+
+::-webkit-scrollbar-thumb:hover {
+  background: #4b5563;
+}
+
+::selection {
+  background: rgba(99, 102, 241, 0.3);
+}