POST /auth/providers/:provider. outcome says what happened: signed in to a linked account,
linked to an existing customer with the same email (only when the provider confirms it; Klarna
and Google do, Microsoft does not), or created a new account. "pending-approval" (HTTP 202)
means a new account awaits manual approval and carries no tokens.
A 409 IDENTITY_EMAIL_NOT_VERIFIED means a customer with that email exists and the provider did
not confirm the address: let the customer sign in with email, then call linkProvider.
POST /auth/providers/:provider.
outcomesays what happened: signed in to a linked account, linked to an existing customer with the same email (only when the provider confirms it; Klarna and Google do, Microsoft does not), or created a new account. "pending-approval" (HTTP 202) means a new account awaits manual approval and carries no tokens.A 409 IDENTITY_EMAIL_NOT_VERIFIED means a customer with that email exists and the provider did not confirm the address: let the customer sign in with email, then call
linkProvider.