StripeKit - List Subscriptions By Customer

`kit.subscriptions.listByCustomer()`

Lists all subscriptions belonging to a customer, optionally filtered by status.

Field	Type	Required	Description
`customerId`	`string`	Yes	The customer to list subscriptions for.
`status`	`string\|null`	No	A Stripe subscription status filter, for example `'active'`, `'trialing'`, `'past_due'`, `'canceled'`, `'all'`. Omit to use Stripe's default (non-canceled subscriptions).

A plain list of records, same shape as retrieve() per item:

Exception	When
`StripeOperationError`	The customer ID does not exist.

This call does not write to your storage adapter.