message: fix(server): Handle empty handler input / output mappings
diff: @@ -56,11 +56,18 @@ function preFormatHandler(
  action: {
  ref: refAgent.getAliasRef(ContributionType.Action, ref),
  settings: null,
  - ...actionMappings,
  + ...effectiveActionMappings(actionMappings),
  },
  };
  }
  +function effectiveActionMappings({ input, output }) {
  + return {
  + input: !isEmpty(input) ? input : undefined,
  + output: !isEmpty(output) ? output : undefined,
  + };
  +}
  +
  function extractFunctions(mappings: { [name: string]: any }): string[] {
  return !isEmpty(mappings)
  ? MapperUtils.functions.parseAndExtractReferencesInMappings(mappings)
  