feat(editor): add WSPV (Spell Variant) — 113th open format

Novel replacement for the implicit context-conditional
spell substitution rules vanilla WoW encoded across
SpellSpecificType, SpellEffect.EffectMechanic override
fields, and the proc-modified spell tables in
SpellProcEvent. Each entry binds one base spell to a
variant spell that activates when a runtime condition
is met (player in a specific stance, talent talented,
racial buff active, weapon equipped, aura present).

Six conditionKind values cover the full substitution
surface: Stance / Form / Talent / Race / EquippedWeapon
/ AuraActive. The conditionValue field is polymorphic —
its semantics depend on conditionKind (a stance spellId,
a talentId, a race bit, etc.). The spell-cast pipeline
iterates findByBaseSpell at cast time and picks the
highest-priority variant whose condition is satisfied,
falling through to the base spell if none matches.

Three preset emitters demonstrating the pattern:
makeWarriorStance (4 stance-conditional Warrior
variants — Heroic Strike Berserker damage bonus,
Battle baseline, Mocking Blow Defensive AoE taunt,
Pummel Berserker-only gate), makeTalentMod (4 talent-
modified variants — Frostbolt + Brain Freeze instant,
Lava Burst + Flame Shock auto-crit, Earth Shield +
Improved bonus heal, Ferocious Bite + Berserk),
makeRacial (4 race-gated racials — Stoneform Dwarf,
War Stomp Tauren, Berserking Troll, Will of the
Forsaken).

Validator's most novel check is the (baseSpell,
conditionKind, conditionValue, priority) 4-tuple
uniqueness — two variants with all four matching
would tie at runtime and resolve non-deterministically
(the spell-cast pipeline's std::sort by priority is
stable but the underlying iteration order is undefined
when priorities tie). Packs the tuple into 64 bits
(base 32 | value 16 | kind 8 | prio 8) for set lookup.

Format count 112 -> 113. CLI flag count 1213 -> 1218.

tools/editor/cli_list_formats.cpp

@@ -137,6 +137,7 @@ constexpr FormatRow kFormats[] = {
     {"WMNL", ".wmnl",  "worldmap",  "WorldMapTransforms.dbc + Overlay",   "Minimap multi-level catalog (vertical zones)"},
     {"WPCR", ".wpcr",  "pets",      "Spell.dbc pet ops + npc_text stable","Pet care + action catalog (Hunter / Warlock / stable mgmt)"},
     {"WMVC", ".wmvc",  "cinematic", "embedded cinematic credit-roll blob","Movie credits roll catalog (per-cinematic)"},
+    {"WSPV", ".wspv",  "spells",    "implicit Spell.dbc context overrides","Spell variant catalog (stance/talent/racial substitution)"},
 
     // Additional pipeline catalogs without the alternating
     // gen/info/validate CLI surface (loaded by the engine