feat(editor): add WIFS (Item Flag Set) open catalog format

Open replacement for the bit-flag meanings used in Item.dbc /
item_template.Flags. Documents every individual bit of the
32-bit item flags field with a human-readable name, description,
kind classification, and is-positive hint.

WoW's Item.dbc Flags field packs ~25 bits of metadata like
Heroic, Lootable, NoLoot, Conjured, BindOnPickup, BindOnEquip —
each controlling a specific gameplay behavior. The hardcoded
client knows what each bit means via a switch statement; this
catalog exposes that table to data-driven editors so:
  - server admins can document custom flag bits
  - tooltip generators can decode "why is this item soulbound?"
    via flag-name lookup (decode(0x40240000) returns
    ["Heroic", "BindOnPickup", "Unique"])
  - validators can warn about contradictory flag combinations

Seven flagKind values classify the bit families (Quality / Drop
/ Trade / Magic / Account / Server / Misc), and an isPositive
hint tells UIs whether the flag enhances the item (green) or
restricts it (red).

Cross-references back to WIT (decodes WIT.flags into the
matching named flag list) and WIQR (validators can pair Heroic
flag with WIQR Epic+ quality requirement).

Three preset emitters: --gen-ifs (8 canonical Item.dbc bits
matching the standard 3.3.5a constants), --gen-ifs-binding (5
binding-related flags BindOnPickup / BindOnEquip / etc — all
restrictive so isPositive=0), --gen-ifs-server (5 server-custom
bits in the upper range demonstrating how to overlay extra
metadata without colliding with Blizzard's bits).

Validation enforces id+name+bitMask presence, flagKind 0..6, no
duplicate ids, no duplicate bitMasks (collision means engine
would only honor first matching name when decoding); warns on
multi-bit masks (unusual — usually want individual bits).

decode(flagsValue) is the engine helper that expands a raw
flags integer into its named flag list — used directly by the
tooltip generator and item info renderers. Wired through the
cross-format table; WIFS appears automatically in all 16
cross-format utilities. Format count 85 -> 86; CLI flag count
1018 -> 1023.

tools/editor/cli_arg_required.cpp

@@ -263,6 +263,8 @@ const char* const kArgRequired[] = {
     "--gen-scs", "--gen-scs-weapon", "--gen-scs-riding",
     "--info-wscs", "--validate-wscs",
     "--export-wscs-json", "--import-wscs-json",
+    "--gen-ifs", "--gen-ifs-binding", "--gen-ifs-server",
+    "--info-wifs", "--validate-wifs",
     "--gen-weather-temperate", "--gen-weather-arctic",
     "--gen-weather-desert", "--gen-weather-stormy",
     "--gen-zone-atmosphere",