Add Telegram notification on every new paid order

Sends to the monitoring bot immediately when payment is confirmed:
- Customer name and email
- Service/slug ordered
- Total amount (includes all fees: service + formation + state + addons)
- Payment method
- Order number and type

Fire-and-forget — never blocks the payment flow.
Requires TELEGRAM_BOT_TOKEN and TELEGRAM_CHAT_ID env vars on API container.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

docker-compose.yml

@@ -48,6 +48,8 @@ services:
       - LISTMONK_URL=http://listmonk:9000
       - LISTMONK_USER=${LISTMONK_USER:-admin}
       - LISTMONK_PASSWORD=${LISTMONK_PASSWORD}
+      - TELEGRAM_BOT_TOKEN=${TELEGRAM_BOT_TOKEN}
+      - TELEGRAM_CHAT_ID=${TELEGRAM_CHAT_ID}
     depends_on:
       - api-postgres
     restart: unless-stopped