fix(SDK-1274): disable invalid payment dates in the off-cycle picker

[krisxcrash]

Fixes SDK-1274 (Medium, Pay v2 / RRoP Test Fest).

Root cause

OffCyclePayPeriodDateFormPresentation rendered the payment-date field as a bare <DatePickerField name="checkDate" ... /> with no minDate, so the earliest-valid-check-date rule existed only as a submit-time validation error. You could pick a past date, submit, and only then be told it was invalid. Legacy gws-flows disables invalid dates in the picker.

The bound was already being computed — OffCycleCreation gets { minCheckDate, today } from useOffCyclePayPeriodDateValidation and feeds it to the zod resolver as isCheckOnly ? today : minCheckDate. It just never reached the field. minDate is already on DatePickerProps and passes straight through DatePickerFieldProps, so the plumbing existed too.

(Confirmed "Payment date" is the checkDate field — Payroll.OffCyclePayPeriodDateForm.json → checkDateLabel.)

Fix

Thread both dates container → presentation, matching the container/presentation split used elsewhere here, and apply the same expression the resolver uses:

minDate={isCheckOnly ? minCheckOnlyDate : minCheckDate}

Reusing the resolver's own expression is what makes the second AC hold — picker and validation cannot drift, so a date the picker allows can never fail validation on submit. Checking "check-only payroll" widens the bound back to today, live.

Testing

Two new cases in OffCycleCreation.test.tsx, following the calendar-aria-disabled pattern the DatePicker UI tests already use. System time is pinned to Wed Sep 2 2026 (so + 2 mocked business days = Fri Sep 4) because the bound derives from today:

• the payment-date calendar disables Sep 3 and allows Sep 4
• toggling check-only relaxes the bound: Sep 2 becomes selectable, Sep 1 stays disabled

I verified both tests fail when the minDate line is removed, so they guard the fix rather than merely passing.

npx vitest run src/components/Payroll — 627 pass. npm run tsc, eslint, prettier — clean. Stories updated with fixed date bounds so they stay deterministic.

Same class of gap, deliberately not fixed here

Both are outside this ticket's AC — happy to file them:

• TransitionCreationPresentation has the identical missing minDate on its own checkDate, and TransitionCreation already computes minCheckDate. Same bug, different flow.
• Correction payrolls forbid a future startDate (enforced in the schema) with no maxDate on that picker.