feat(editor): add WCMG (Combat Maneuver Group) open catalog format

Novel replacement for the hardcoded class-mutex tables
the WoW client uses to grey out incompatible action-bar
buttons. Each entry is one mutually-exclusive spell
group: Warrior stances (Battle/Defensive/Berserker),
Druid shapeshift forms (Bear/Cat/Travel/Tree/Moonkin),
Hunter aspects (Hawk/Cheetah/Pack/Viper/Dragonhawk/Beast/
Wild), DK presences (Frost/Unholy/Blood). The action-bar
update path uses the catalog to know which spells share
a mutex bucket and clear "currently active" outlines
when a sibling is cast.

Six categoryKind enum values (Stance / Form / Aspect /
Presence / Posture / Sigil) and variable-length members[]
array of spell IDs (refs WSPL). Three presets:
makeWarrior (Warrior 3-stance), makeDruid (5 shapeshift
+ 2 flight, separate buckets so flying isn't broken by
Cat Form), makeAllMutex (cross-class catalog with one
representative group per mutex-having class).

Validator catches several authoring bugs: empty members[]
(group has nothing to switch between), spellId 0,
duplicate spellId within a group, and — most usefully —
the same spellId appearing in two different exclusive
groups (which would make the action-bar mutex
undecidable: which group's outline does the bar use?).
Warns on single-member groups (mutex with one element
has no exclusion to enforce).

Format count 98 -> 99 (one short of triple-digit
milestone). CLI flag count 1112 -> 1117.

tools/editor/cli_format_table.cpp

@@ -101,6 +101,7 @@ constexpr FormatMagicEntry kFormats[] = {
     {{'W','G','R','P'}, ".wgrp",  "social",    "--info-wgrp",      "Group composition catalog"},
     {{'W','H','R','T'}, ".whrt",  "social",    "--info-whrt",      "Hearthstone bind point catalog"},
     {{'W','S','C','B'}, ".wscb",  "server",    "--info-wscb",      "Server channel broadcast catalog"},
+    {{'W','C','M','G'}, ".wcmg",  "spells",    "--info-wcmg",      "Combat maneuver group catalog"},
     {{'W','F','A','C'}, ".wfac",  "factions",  nullptr,            "Faction catalog"},
     {{'W','L','C','K'}, ".wlck",  "locks",     nullptr,            "Lock catalog"},
     {{'W','S','K','L'}, ".wskl",  "skills",    nullptr,            "Skill catalog"},