feat(editor): WPRC JSON round-trip closure

Adds --export-wprc-json / --import-wprc-json with the established
readEnumField template factoring int+name dual encoding for
triggerEvent ("onhit"/"oncrit"/"oncast"/"ontakedamage"/"onheal"/
"ondodge"/"onparry"/"onblock"/"onkill").

All 3 presets (weapon/ret/rage) byte-identical binary roundtrip
OK including the rage preset's previously-fixed Berserker Rage
proc rule (sourceSpellId=18499, procEffectSpellId=23691 distinct).

Live-tested self-loop validator a second time: re-introduced the
Berserker Rage source==effect bug via JSON edit (set effect back
to 18499). Validator correctly errored: "sourceSpellId ==
procEffectSpellId=18499 on OnCast trigger — infinite proc loop
(effect re-casts itself)". Confirms the round-trip path
preserves the self-loop guard and that the validator is ready
to catch this class of bug whenever a hand-edit reintroduces it.

CLI flag count 1443 -> 1445.

tools/editor/cli_arg_required.cpp

@@ -424,6 +424,7 @@ const char* const kArgRequired[] = {
     "--export-wirc-json", "--import-wirc-json",
     "--gen-prc-weapon", "--gen-prc-ret", "--gen-prc-rage",
     "--info-wprc", "--validate-wprc",
+    "--export-wprc-json", "--import-wprc-json",
     "--gen-weather-temperate", "--gen-weather-arctic",
     "--gen-weather-desert", "--gen-weather-stormy",
     "--gen-zone-atmosphere",