Show cash-flow budget remaining behind a toggle

Summary

Exposed section remaining fields on the monthly dashboard API and showed bare_minimum_remaining, subscriptions_budget_remaining, and daily_budget_remaining on the Cash Flow page behind a collapsed Budget remaining toggle. Rebased the feature branch onto main after the earlier cash-flow stats PR was squash-merged.

Decisions

• Keep the extra remaining fields collapsed under a Budget remaining toggle instead of always-visible debug copy
• Label the debug metrics with API field names so they match GET /api/dashboard/monthly

Learnings

• After a squash merge, rebase onto main and skip commits whose patches are already upstream instead of resolving stale conflicts
• git push –force-with-lease rewrites a published branch only if the remote tip still matches the last fetch