feat: add --argumentStyle option

* feat: add --argumentStyle option

* fix: handle empty params case, add tests

* fix(gen): generate demo

* fix: follow upstream changes

README.md

@@ -36,6 +36,7 @@ Options:
 --optimistic
 --useEnumType
 --mergeReadWriteOnly
+--argumentStyle=<positional | object> (default: positional)
 ```
 
 Where `<spec>` is the URL or local path of an OpenAPI or Swagger spec (in either json or yml) and `<filename>` is the location of the `.ts` file to be generated. If the filename is omitted, the code is written to stdout.
@@ -48,6 +49,8 @@ Where `<spec>` is the URL or local path of an OpenAPI or Swagger spec (in either
 
 - `--mergeReadWriteOnly` by default oazapfs will generate separate types for read-only and write-only properties. This option will merge them into one type.
 
+- `--argumentStyle` if "object" generated functions take single object style argument for parameters and requestBody, by default it's "positional" and parameters are separate as positional arguments
+
 ## Consuming the generated API
 
 For each operation defined in the spec the generated API will export a function with a name matching the `operationId`. If no ID is specified, a reasonable name is generated from the HTTP verb and the path.