Bare L in day of week: description is wrong for all cron types, and the wrong day is scheduled for 0-7 definitions

[austek]

Bare L in the day-of-week field (as opposed to nL) has two separate defects. Scheduling was fixed for Quartz in #142 / 6.0.0, but the description was not, and the fix does not carry over to definitions that number days differently.

1. Description is wrong for every cron type

CronDescriptor d = CronDescriptor.instance(Locale.UK);
CronParser quartz = new CronParser(CronDefinitionBuilder.instanceDefinitionFor(CronType.QUARTZ));
d.describe(quartz.parse("0 0 0 ? * L *"));

Actual: at 00:00 last Sunday of every month
Expected: something like at 00:00 every Saturday

Both halves are wrong — it is not restricted to the last week of the month, and the day is Saturday, not Sunday. The scheduling for QUARTZ is correct (every Saturday: 2025-06-07, 06-14, 06-21, 06-28, 07-05, matching org.quartz.CronExpression 2.5.0 exactly), so this is purely a describer bug and the two surfaces disagree with each other.

2. Wrong day scheduled for definitions with a 0-7 / Monday=1 range

CronParser spring53 = new CronParser(CronDefinitionBuilder.instanceDefinitionFor(CronType.SPRING53));
ExecutionTime.forCron(spring53.parse("0 0 0 ? * L"));

	next 5 executions
QUARTZ	2025-06-07, 06-14, 06-21, 06-28, 07-05 — all Saturday, correct
SPRING53	2025-06-08, 06-15, 06-22, 06-29, 07-06 — all Sunday

Bare L should mean the last day of the week regardless of how the definition numbers its days.

Cause

OnDayOfWeekValueGenerator holds Saturday as a literal in Quartz numbering:

private static final On ON_SATURDAY = new On(new IntegerFieldValue(7));

and generateNoneValues then normalizes that value using the current definition's scheme:

final int requiredDoW = ConstantsMapper.weekDayMapping(mondayDoWValue, ConstantsMapper.JAVA8, on.getTime().getValue());

For QUARTZ (mondayDoWValue = 2, 1=Sun..7=Sat) the literal 7 maps to Saturday, which is why #142 looks fixed. For SPRING53 (mondayDoWValue = 1, plus withIntMapping(7, 0)) the same literal maps to Sunday. The constant is in one numbering but is interpreted in another, so it only happens to be right for Quartz.

Version: both reproduced on master (bac6e86); #2 also affects released 9.2.1 via SPRING53.