Budget: recurring items CRUD, yearly/monthly projections with no-double-count
logic, and full UI (overview, monthly detail, recurring items manager).
Push notifications: Web Push via VAPID keys, triggered on transaction creation
from n8n. Includes service worker handlers, frontend subscription flow, and
a test button on the Dashboard (temporary).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
