Notification upgrades: lifecycle, configurable levels, summaries

- NOTIFY_LEVELS chooses which event levels are sent (default trade,error).
- NOTIFY_LIFECYCLE sends explicit start/stop messages; the kill switch always
  notifies at error level.
- SUMMARY_INTERVAL_MINUTES sends a periodic portfolio summary (equity, per
  strategy P&L, allocation, halted state) via a background task started with
  the run and stopped on stop/kill/shutdown.
- Wires the new vars plus the go-live vars through both compose files and the
  deploy workflow. Adds tests.

.env.example

@@ -65,6 +65,12 @@ TELEGRAM_BOT_TOKEN=
 TELEGRAM_CHAT_ID=
 # Generic webhook: receives POST {"level": "...", "text": "..."}
 NOTIFY_WEBHOOK_URL=
+# Event levels to notify on (comma separated): trade, error, warning, info.
+NOTIFY_LEVELS=trade,error
+# Send explicit start/stop messages.
+NOTIFY_LIFECYCLE=true
+# Periodic portfolio summary every N minutes (0 disables).
+SUMMARY_INTERVAL_MINUTES=0
 
 # --- Web ---
 # Comma separated list, or * in dev