curl -X POST https://api.alguna.io/billing/customer-session/create/portal-link-sharing \ -H "Authorization: Bearer YOUR_API_KEY" \ -H "Content-Type: application/json" \ -d '{ "accountId": "acc_abc123" }'
{ "id": "sess_def456", "sessionToken": "tok_def456...", "sessionUrl": "https://portal.alguna.io/hs/tok_def456..." }