chore(pwa): allow internal split-DNS host on the vite dev server

Add .bergerhouse.net (apex + subdomains) to server.allowedHosts so the dev
PWA is reachable through the reverse proxy / tunnel (e.g.
familysync-dev.bergerhouse.net). Dev-server only; production builds ignore it.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

apps/pwa/vite.config.ts

@@ -44,6 +44,10 @@ export default defineConfig({
     }),
   ],
   server: {
+    // Allow the internal split-DNS domain (and any subdomain) to reach the dev
+    // server through the reverse proxy / tunnel. A leading dot matches the apex
+    // and all subdomains. Dev-server only — production builds ignore this.
+    allowedHosts: ['.bergerhouse.net'],
     proxy: {
       '/health': 'http://localhost:3000',
       '/api': 'http://localhost:3000',