App codegen: remove arg types/interfaces

[krisbitney]

We can simplify app codegen by removing the Args types.

Current method codegen:

export interface TestImport_Module_Args_anotherMethod {
  arg1: Array<Types.String>;
  arg2: Types.Int32;
}

async anotherMethod(
  args: TestImport_Module_Args_anotherMethod,
  client?: CoreClient,
  env?: Record<string, unknown>,
  uri?: string,
): Promise<InvokeResult<Types.Int32>>

Proposed method codegen:

async anotherMethod(
  arg1: Array<Types.String>,
  arg2: Types.Int32,
  _options: {
    client?: CoreClient,
    env?: Record<string, unknown>,
    uri?: string,
  }
): Promise<InvokeResult<Types.Int32>>