fix: skip short months for nW day-of-month (#715)

[arimu1]

Summary

Fixes #715

nW (nearest weekday to the nth of the month) threw DateTimeException when the candidate month was shorter than n (e.g. 31W in June), because OnDayOfMonthValueGenerator called LocalDate.of(year, month, dayOfMonth) before checking month length.

Changes

• Guard: if dayOfMonth > lengthOfMonth, throw NoSuchValueException so the scheduler skips that month (same approach as the L branch, and aligned with Quartz).
• Sunday last day: when n is the last day of a long month and falls on Sunday, resolve to Friday (n - 2) so weekday adjustment matches Quartz (e.g. 2025-08-31 → 2025-08-29).

Reproduction (now fixed)

CronParser parser = new CronParser(CronDefinitionBuilder.instanceDefinitionFor(CronType.QUARTZ));
ExecutionTime et = ExecutionTime.forCron(parser.parse("0 0 0 31W * ?"));
et.nextExecution(ZonedDateTime.parse("2025-06-01T00:00:00Z"));
// → 2025-07-31 (June/Sep/Nov/Feb skipped)

Test plan

• OnDayOfMonthValueGeneratorWTest — short-month no-value + last-day Sunday → Friday
• Issue715Test — Quartz 31W sequence matches reference; SPRING53 skips June
• Full suite: 809 tests, 0 failures (Temurin 21)