Please use double quotes in the generated CURL command for windows support

The generated curl command used single quotes but that doesn't work for Windows users that have shell. Linux supports both single and double quotes. Changing `--header=''` to `--header=""` will enable windows users with curl to use it too :).

Start at the TypeScript entry point that generates the curl command and trace how header arguments are quoted. Change the generated header syntax from single to double quotes, then verify that the Windows-compatible command uses double-quoted values while preserving valid Linux output.

索引モデルが issue の本文から書いたものです。