Reapply "feat(loyalty): EnakPoint & EnakCoin" (#32)

This reverts commit 4e24f9bbb0.

internal/contract/customer_pin_contract.go

@@ -0,0 +1,39 @@
+package contract
+
+// Requests of /customer/pin and /marketing/customers/:id/pin (docs/prd-point-coin.md
+// F11). PINs are strings so a leading zero is kept.
+
+type RequestPinOtpRequest struct {
+	// pin_setup or pin_reset.
+	Purpose string `json:"purpose" binding:"required"`
+}
+
+type CreateCustomerPinRequest struct {
+	OtpToken   string `json:"otp_token" binding:"required"`
+	OtpCode    string `json:"otp_code" binding:"required"`
+	Pin        string `json:"pin" binding:"required"`
+	ConfirmPin string `json:"confirm_pin" binding:"required"`
+}
+
+type ChangeCustomerPinRequest struct {
+	OldPin     string `json:"old_pin" binding:"required"`
+	Pin        string `json:"pin" binding:"required"`
+	ConfirmPin string `json:"confirm_pin" binding:"required"`
+}
+
+type ResetCustomerPinRequest = CreateCustomerPinRequest
+
+type RemoveCustomerPinRequest struct {
+	Reason string `json:"reason" binding:"required"`
+}
+
+// IssuePaymentCodeRequest is POST /customer/wallet/payment-code.
+type IssuePaymentCodeRequest struct {
+	Pin string `json:"pin" binding:"required"`
+}
+
+// PayWithPointsRequest is POST /customer/orders/:id/pay-with-points.
+type PayWithPointsRequest struct {
+	Points int64  `json:"points" binding:"required,min=1"`
+	Pin    string `json:"pin" binding:"required"`
+}