feat: [css] A new field headline_offer_installment is added to mess…

…age `.google.shopping.css.v1.Attributes` (#5765)

* feat: A new field `headline_offer_installment` is added to message `.google.shopping.css.v1.Attributes`
feat: A new field `headline_offer_subscription_cost` is added to message `.google.shopping.css.v1.Attributes`
feat: A new message `HeadlineOfferSubscriptionCost` is added
feat: A new message `HeadlineOfferInstallment` is added
feat: A new enum `SubscriptionPeriod` is added

PiperOrigin-RevId: 688649184

Source-Link: googleapis/googleapis@c8a7261

Source-Link: googleapis/googleapis-gen@3dcef19
Copy-Tag: eyJwIjoicGFja2FnZXMvZ29vZ2xlLXNob3BwaW5nLWNzcy8uT3dsQm90LnlhbWwiLCJoIjoiM2RjZWYxOWUzMDdiNjc5YTNmNmM4ODFkNzlmMDY0ZTg4NWZkNTJmZCJ9

* 🦉 Updates from OwlBot post-processor

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

---------

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>
Co-authored-by: sofisl <55454395+sofisl@users.noreply.github.com>

packages/google-shopping-css/README.md

@@ -44,7 +44,7 @@ Google APIs Client Libraries, in [Client Libraries Explained][explained].
 1.  [Select or create a Cloud Platform project][projects].
 1.  [Enable billing for your project][billing].
 1.  [Enable the CSS API API][enable_api].
-1.  [Set up authentication with a service account][auth] so you can access the
+1.  [Set up authentication][auth] so you can access the
     API from your local workstation.
 
 ### Installing the client library
@@ -203,4 +203,4 @@ See [LICENSE](https://github.com/googleapis/google-cloud-node/blob/main/LICENSE)
 [projects]: https://console.cloud.google.com/project
 [billing]: https://support.google.com/cloud/answer/6293499#enable-billing
 [enable_api]: https://console.cloud.google.com/flows/enableapi?apiid=css.googleapis.com
-[auth]: https://cloud.google.com/docs/authentication/getting-started
+[auth]: https://cloud.google.com/docs/authentication/external/set-up-adc-local

packages/google-shopping-css/protos/google/shopping/css/v1/css_product_common.proto

@@ -205,6 +205,13 @@ message Attributes {
 
   // Custom label 4 for custom grouping of items in a Shopping campaign.
   optional string custom_label_4 = 50;
+
+  // Number and amount of installments to pay for an item.
+  HeadlineOfferInstallment headline_offer_installment = 51;
+
+  // Number of periods (months or years) and amount of payment per period
+  // for an item with an associated subscription contract.
+  HeadlineOfferSubscriptionCost headline_offer_subscription_cost = 52;
 }
 
 // The certification for the product. Use the this attribute to describe
@@ -336,3 +343,42 @@ message CssProductStatus {
   // 8601](http://en.wikipedia.org/wiki/ISO_8601) format.
   google.protobuf.Timestamp google_expiration_date = 7;
 }
+
+// The SubscriptionCost of the product.
+message HeadlineOfferSubscriptionCost {
+  // The type of subscription period.
+  // Supported values are:
+  //   * "`month`"
+  //   * "`year`"
+  SubscriptionPeriod period = 1;
+
+  // The number of subscription periods the buyer has to pay.
+  int64 period_length = 2;
+
+  // The amount the buyer has to pay per subscription period.
+  google.shopping.type.Price amount = 3;
+}
+
+// A message that represents installment.
+message HeadlineOfferInstallment {
+  // The number of installments the buyer has to pay.
+  int64 months = 1;
+
+  // The amount the buyer has to pay per month.
+  google.shopping.type.Price amount = 2;
+
+  // The up-front down payment amount the buyer has to pay.
+  google.shopping.type.Price downpayment = 3;
+}
+
+// The subscription period of the product.
+enum SubscriptionPeriod {
+  // Indicates that the subscription period is unspecified.
+  SUBSCRIPTION_PERIOD_UNSPECIFIED = 0;
+
+  // Indicates that the subscription period is month.
+  MONTH = 1;
+
+  // Indicates that the subscription period is year.
+  YEAR = 2;
+}