feat(editor): add WBOS (Boss Encounter Definition) open catalog format

Open replacement for AzerothCore's instance_encounter SQL table
plus the per-boss script bindings. Defines raid boss encounter
metadata: which creature is the boss, which map and difficulty
variant it lives in, how many phases the encounter has, the
soft-enrage timer and berserk spell, recommended group size, and
item level.

One entry per (boss × difficulty) combination. Lord Marrowgar in
10-Normal ICC is one entry; Lord Marrowgar in 25-Heroic ICC is a
separate entry with a higher recommendedItemLevel and a different
difficultyId pointing into WCDF.

This format ties together five other catalogs into a coherent
encounter description:
  - WCRT for the boss creature template
  - WMS for the instance map
  - WCDF for difficulty routing (10/25/H10/H25 variants)
  - WSPL for the berserk spell that fires at enrage
  - WACR for achievement criteria like "kill The Lich King in
    25-Heroic" that point back via KillCreature targetId

findByMap(mapId) returns all encounters in one raid instance,
sorted by their catalog order — used by the Encounter Journal
UI and instance lockout logic. findByBossCreature(bossId)
returns all difficulty variants of one boss.

Three preset emitters: --gen-bos (3 5-man dungeon bosses with
no soft-enrage), --gen-bos-raid10 (4 ICC 10-Normal bosses
including 5-phase Lich King with 15min hard enrage via Fury of
Frostmourne 72546), --gen-bos-world (2 outdoor world bosses
with 25-player size + no difficulty).

Validation enforces id+name+boss+map+phases+size presence, no
duplicate ids; warns on:
  - non-standard requiredPartySize (canonical sizes are
    5/10/25/40)
  - berserkSpellId set without enrageTimerMs (spell never fires)
  - enrageTimerMs > 30 minutes (sanity check)

Wired through the cross-format table; WBOS appears in all 18
cross-format utilities. Format count 90 -> 91; CLI flag count
1055 -> 1060.

tools/editor/cli_arg_required.cpp

@@ -279,6 +279,8 @@ const char* const kArgRequired[] = {
     "--gen-cmr", "--gen-cmr-city", "--gen-cmr-boss",
     "--info-wcmr", "--validate-wcmr",
     "--export-wcmr-json", "--import-wcmr-json",
+    "--gen-bos", "--gen-bos-raid10", "--gen-bos-world",
+    "--info-wbos", "--validate-wbos",
     "--gen-weather-temperate", "--gen-weather-arctic",
     "--gen-weather-desert", "--gen-weather-stormy",
     "--gen-zone-atmosphere",