`unpaid` subscription status undocumented

[Glench]

Discussed in #221

^{Originally posted by ba32107 July 7, 2024}
In dev mode, I can set an unpaid status:

This status is not present in the main README or this doc:
https://github.com/Glench/ExtPay/blob/main/docs/how_subscriptions_work.md

It's not really clear what the difference is between past_due and unpaid. The Stripe docs say:

If subscription collection_method=send_invoice it becomes past_due when its invoice is not paid by the due date, and canceled or unpaid if it is still not paid by an additional deadline after that.

From this I can sort of understand the difference, but it's never mentioned anywhere in the ExtPay docs that the subscriptionStatus property mimicks the Stripe API's values. So I think this additional value should be documented in this repo.

Thanks!

[ba32107]

Forgot to mention in my original report, the type definition also lacks this property:

Thanks!

[ba32107]

Also, I know it's not related to this issue, but the email property is also missing on the User typescript interface. I've seen it was already added, but the NPM package is still outdated, could it be released soon? Thanks!