ops: finalize production domain and hardware benchmark tooling

Add /version.json build identity, deploy 16e7930 release markers,
DNS/Named Tunnel prep docs, portable browser benchmark, and replay
stability probe. Keep Quick Tunnel until permanent domain cutover.

Co-authored-by: Cursor <cursoragent@cursor.com>

docs/DEMO_RUNBOOK.md

@@ -5,6 +5,7 @@
 **Рабочий публичный URL (временный):** Quick Tunnel — см. `PRODUCTION_DEPLOYMENT_REPORT.md`
 **Ожидаемый постоянный домен:** https://arhipovdan.ru/ — **BLOCKED_EXTERNAL** (`PUBLIC_DOMAIN_DIAGNOSTIC.md`)
 **Локальный production:** http://127.0.0.1:3100/
+**Проверка версии:** `curl -s http://127.0.0.1:3100/version.json`
 **Репозиторий:** `/home/coder/arhipovdan/app`
 
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