message: refactor: Separate out argMapper types for readability
diff: -export type ArgMapping<PactOptions> = {
  - [Key in keyof PactOptions]:
  - | {
  +type BasicMapping = {
  arg: string;
  mapper: 'string' | 'flag';
  - }
  - | {
  +};
  +
  +type IgnoreAndWarn = {
  warningMessage: string;
  - }
  - | ((arg: NonNullable<PactOptions[Key]>) => string[]);
  +};
  +
  +type FunctionMapping<T> = (arg: NonNullable<T>) => string[];
  +
  +export type ArgMapping<PactOptions> = {
  + [Key in keyof PactOptions]:
  + | BasicMapping
  + | IgnoreAndWarn
  + | FunctionMapping<PactOptions[Key]>;
  };
  