fix: increase initial bank sync window from 90 to 120 days (#170)

90 days missed transactions from late December for users connecting
in early April.

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/(dashboard)/settings/banking/page.tsx

@@ -34,7 +34,7 @@ export default function BankingSettingsPage() {
         fetch('/api/extensions/ext/enable-banking/sync', {
           method: 'POST',
           headers: { 'Content-Type': 'application/json' },
-          body: JSON.stringify({ connection_id: connectionId, days_back: 90 }),
+          body: JSON.stringify({ connection_id: connectionId, days_back: 120 }),
         })
           .then(res => res.json())
           .then(data => {