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

Closes the WMAL open-format loop with --export-wmal-json /
--import-wmal-json, mirroring the JSON pairs added for
every other novel binary format. All 28 binary formats
added since WOL now have full JSON round-trip authoring.

Each template round-trips all 11 scalar fields plus the
variable-length attachments array. categoryId emits dual
int + name forms (quest / auction / gm / achievement /
event / raffle / script / returned).

Verified byte-identical round-trip on the holiday preset
(4 templates with full WIT itemId attachments matching
WTKN seasonal token IDs preserved through the JSON layer).

Adds 2 flags (644 documented total now).

tools/editor/cli_arg_required.cpp

@@ -100,6 +100,7 @@ const char* const kArgRequired[] = {
     "--export-wbgd-json", "--import-wbgd-json",
     "--gen-mail", "--gen-mail-holiday", "--gen-mail-auction",
     "--info-wmal", "--validate-wmal",
+    "--export-wmal-json", "--import-wmal-json",
     "--gen-gems", "--gen-gems-set", "--gen-gems-enchants",
     "--info-wgem", "--validate-wgem",
     "--gen-weather-temperate", "--gen-weather-arctic",