docs: backlog for agent version compliance and remote updates

Add agent-update-backlog.md and roadmap v0.7 outline for SAC-driven
agent version tracking and remote update initiation.

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

docs/todo-2026-05-29.md

@@ -84,5 +84,6 @@ UseSAC=exclusive→ только SAC ingest; TG/email = настройки SAC (
 
 - [TZ.md](TZ.md) §4.6 F-NOT-01 … F-NOT-05
 - [agent-integration.md](agent-integration.md) — режимы UseSAC
+- [agent-update-backlog.md](agent-update-backlog.md) — **ToDo:** версии агентов и удалённое обновление из SAC
 - `backend/app/config.py` — `telegram_*`
 - `backend/app/services/telegram_notify.py`