feat(editor): add WPCD JSON round-trip authoring workflow

Closes the WPCD open-format loop with --export-wpcd-json /
--import-wpcd-json, mirroring the JSON pairs added for
every other novel binary format. All 31 binary formats
added since WOL now have full JSON round-trip authoring.

Each condition round-trips all 9 scalar fields. Two
enum-typed fields emit dual int + name forms:
  • kind       (true / false / quest-done / has-item /
                 min-level / class / event / area / title / ...)
  • aggregator (and / or)

Verified byte-identical round-trip on the gated preset
(5 conditions in 2 groups demonstrating both AND and OR
aggregation, with full polymorphic targetId / minValue /
maxValue payload preserved through the JSON layer).

Adds 2 flags (665 documented total now).

tools/editor/cli_arg_required.cpp

@@ -109,6 +109,7 @@ const char* const kArgRequired[] = {
     "--export-wgld-json", "--import-wgld-json",
     "--gen-conditions", "--gen-conditions-gated", "--gen-conditions-event",
     "--info-wpcd", "--validate-wpcd",
+    "--export-wpcd-json", "--import-wpcd-json",
     "--gen-pets", "--gen-pets-hunter", "--gen-pets-warlock",
     "--info-wpet", "--validate-wpet",
     "--gen-weather-temperate", "--gen-weather-arctic",