`GET /billing/invoices` — the org's Stripe invoice history (every billing period since the subscription started), newest first, each with a Stripe-hosted page + downloadable PDF link. Served through the management API, which holds the org's Stripe customer. Empty (not an error) when the org has never had a Stripe customer; a management API that does not answer is a `503`, never an empty list.

curl -X GET "https://example.com/billing/invoices"

{  "data": [    {      "amount_due": 0,      "amount_paid": 0,      "created_at": "string",      "currency": "string",      "hosted_invoice_url": "string",      "id": "string",      "invoice_pdf": "string",      "number": "string",      "period_end": "string",      "period_start": "string",      "status": "string"    }  ],  "page": 0,  "page_size": 0,  "total": 0,  "total_pages": 0}