Auto-register scheduled messages event in Cronicle on startup

On startup raggr calls the Cronicle API (CRONICLE_URL + CRONICLE_API_KEY)
and creates a 'Scheduled Messages Trigger' shell event if it doesn't exist,
replacing the need to configure it manually in the Cronicle UI.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docker-compose.yml

@@ -61,6 +61,9 @@ x-raggr-common: &raggr-common
     - ALLOWED_IMESSAGE_NUMBERS=${ALLOWED_IMESSAGE_NUMBERS}
     - SIMBAKIT_URL=${SIMBAKIT_URL:-http://simbakit:8585}
     - CRON_SECRET=${CRON_SECRET}
+    - CRONICLE_URL=${CRONICLE_URL:-http://cronicle:3012}
+    - CRONICLE_API_KEY=${CRONICLE_API_KEY}
+    - RAGGR_INTERNAL_URL=${RAGGR_INTERNAL_URL:-http://raggr-green:8080}
   depends_on:
     postgres:
       condition: service_healthy