collapseToFirstPage method
The ARRIVAL-edge refresh (U1): like refresh but BYPASSES the
deep-page guard — a real incoming payment (rare, user-meaningful; the
caller gates on newTxCount > 0) is worth collapsing pagination back to
page 1, because the alternative is a deep-paged list that NEVER shows the
new payment (both refresh edges no-op deep-paged, and nothing else
re-reads until a session swap). No-blanking holds: the current rows stay
visible until the fresh page lands.
Implementation
Future<void> collapseToFirstPage() => _reloadFirstPage();