Subscription Recurring Expense Tracker

Real billing-cycle math, not guesswork: monthly/yearly renewals walk forward in true calendar months/years (a Jan 31 start clamps to Feb 28/29); weekly/custom intervals use exact day counts. Exact total-spent and spent-this-year figures from real charge history, a labeled avg/mo for plan comparison, and "likely forgotten" flags after 60+ unconfirmed days. Zero dependencies, fully offline, JSON export/import. Playwright-verified vs. independent reimplementation. (AI-assisted; verified working.)