feat(pipeline): add WHOL (Wowee Holiday) catalog

44th open format — replaces Holidays.dbc + HolidayDescriptions.dbc
+ HolidayNames.dbc plus the AzerothCore-style game_event SQL
tables. Defines time-gated world events: seasonal holidays
(Hallow's End / Brewfest / Winter Veil), weekly call-to-arms BG
bonuses, world-PvP windows (Wintergrasp), one-shot specials, and
recurring daily / weekly resets. Each holiday has a recurrence
rule (Annual / Monthly / WeeklyRecur / OneTime), a calendar
window (startMonth + startDay + durationHours), and optional
cross-refs to a feature creature, an intro quest, and a token /
item reward issued during the window.

Cross-references with prior formats — holidayQuestId points at
WQT.questId, bossCreatureId points at WCRT.creatureId,
itemRewardId points at WIT.itemId, and areaIdGate / mapIdGate
point at WMS.areaId / WMS.mapId.

CLI: --gen-holidays (3 seasonal starter), --gen-holidays-weekly
(3 weekly BG call-to-arms windows), --gen-holidays-special (3
world-PvP / lunar / children events), --info-whol, --validate-whol
with --json variants. Validator catches id=0/duplicates, kind /
recurrence out of range, durationHours=0, invalid month/day for
non-weekly recurrence, and calendar-only events (no quest +
boss + reward) as a warning.

tools/editor/cli_arg_required.cpp

@@ -128,6 +128,8 @@ const char* const kArgRequired[] = {
     "--gen-vehicles", "--gen-vehicles-siege", "--gen-vehicles-flying",
     "--info-wvhc", "--validate-wvhc",
     "--export-wvhc-json", "--import-wvhc-json",
+    "--gen-holidays", "--gen-holidays-weekly", "--gen-holidays-special",
+    "--info-whol", "--validate-whol",
     "--gen-weather-temperate", "--gen-weather-arctic",
     "--gen-weather-desert", "--gen-weather-stormy",
     "--gen-zone-atmosphere",