feat(editor): add WMAT (Item Material) open catalog format

Open replacement for Blizzard's Material.dbc plus the Material
and SheatheType fields in ItemDisplayInfo.dbc. Defines the
material categorization that items reference (Cloth / Leather /
Mail / Plate / Wood / Steel / Crystal / Ethereal / etc), each
with its own foley sound (played on item use), impact sound
(played on drop / hit), weight category, and material-property
flags (IsBreakable / IsMagical / IsFlammable / IsConductive /
IsHolyCharged / IsCursed).

The engine plays a sword's metallic clang from impactSoundId
when it hits a stone wall, but a cloth tabard makes no such
sound — the difference is exactly the material assigned by this
catalog. Every armor and weapon item in WIT references a
materialId here.

Twelve materialKind values cover the standard armor classes
(Cloth/Leather/Mail/Plate/Hide), structural materials (Wood /
Stone / Metal), and special categories (Liquid / Organic /
Crystal / Ethereal). Three weight tiers (Light / Medium / Heavy)
control encumbrance UI hints.

Cross-references back to WSND (foleySoundId / impactSoundId
reference WSND sound entries) and forward to WIT (item entries
reference materialId here).

Three preset emitters: --gen-mat (5 armor materials matching
WoW's armor classes), --gen-mat-weapon (5 weapon materials from
breakable+flammable Wood through enchanted endgame steel),
--gen-mat-magical (4 magical materials with special flags
including the IsHolyCharged anti-undead property).

Validation enforces id+name presence, materialKind 0..11,
weightCategory 0..2, no duplicate ids; warns on:
  - IsHolyCharged + IsCursed both set (engine picks one,
    typically IsCursed wins)
  - Plate kind that's not Heavy weight (canonical violation)
  - Cloth kind that's not Light weight (canonical violation)

Wired through the cross-format table; WMAT appears automatically
in all 11 cross-format utilities. Format count 75 -> 76; CLI flag
count 943 -> 948.

tools/editor/cli_arg_required.cpp

@@ -231,6 +231,8 @@ const char* const kArgRequired[] = {
     "--gen-cdf", "--gen-cdf-wotlk-raid", "--gen-cdf-fiveman",
     "--info-wcdf", "--validate-wcdf",
     "--export-wcdf-json", "--import-wcdf-json",
+    "--gen-mat", "--gen-mat-weapon", "--gen-mat-magical",
+    "--info-wmat", "--validate-wmat",
     "--gen-weather-temperate", "--gen-weather-arctic",
     "--gen-weather-desert", "--gen-weather-stormy",
     "--gen-zone-atmosphere",