Click to Pay proposal 1 (#211)

This approach follows the current way of adding a new token payment
method via a `clicktopay[...]` parameter.

<img width="702" height="833" alt="image"
src="https://github.com/user-attachments/assets/f00a0d0e-9438-4f69-8a6e-f7a026798b4a"
/>

Author: thejspr

website/content/gateway/api_reference/changes/changes.md

@@ -10,6 +10,10 @@ Follow coming changes on the [source code repository](https://github.com/clearha
 
 Sorted by descending timestamp.
 
+#### Add support for Click to Pay
+Starting 2025-10-01, we support Click to Pay as a token framework. Please see
+[Method: token](#method-token) for details.
+
 #### Add minimum amount for Visa captures and refunds
 Starting 2025-05-19, we will enforce a minimum amount of USD 0.005 for captures
 and refunds made with Visa. This is due to USD 0.005 being half a minor, and

website/content/gateway/api_reference/resources/authorizations/authorizations_methods/token.md

@@ -6,8 +6,9 @@ weight: 135
 ---
 #### Method: token
 
-Two token frameworks are supported:
+Three token frameworks are supported:
 
+* `clicktopay`: Click to Pay
 * `token[m4m]`: Mastercard Digital Enablement Service (MDES) for Merchants (M4M)
 * `token[vts]`: Visa Token Service (VTS)
 
@@ -17,6 +18,38 @@ Requirement of some parameters depends on the initiator of the transaction; a pa
 **Notice**: Signing is required to use the `token` payment method.
 {{% /notice %}}
 
+#### Method: Click to Pay
+
+Click to Pay token payment method for both Visa and Mastercard CITs.
+
+{{% description_list %}}
+{{% description_term %}}clicktopay[tan] {{% regex %}}[0-9]{12,19}{{% /regex %}}{{% /description_term %}}
+{{% description_details %}}Token Account Number (TAN) of the token to charge.
+{{% /description_details %}}
+
+{{% description_term %}}clicktopay[expire_month] {{% regex %}}[0-9]{2}{{% /regex %}}{{% /description_term %}}
+{{% description_details %}}Expiry month of token to charge.
+{{% /description_details %}}
+
+{{% description_term %}}clicktopay[expire_year] {{% regex %}}20[0-9]{2}{{% /regex %}}{{% /description_term %}}
+{{% description_details %}}Expiry year of token to charge.
+{{% /description_details %}}
+
+{{% description_term %}}clicktopay[tav] {{% regex %}}[:base64:]{28}{{% /regex %}}{{% /description_term %}}
+{{% description_details %}}Token authentication value, also known as cryptogram.
+{{% /description_details %}}
+
+{{% description_term %}}clicktopay[eci] {{% regex %}}0[57]{{% /regex %}}{{% /description_term %}}
+{{% description_details %}}Zero-padded e-commerce indicator from token flow.
+{{% regex_optional %}}Required for Visa CITs.{{% /regex_optional %}}
+{{% /description_details %}}
+
+{{% description_term %}}clicktopay[3dsecure] {{% regex %}}dictionary{{% /regex %}}{{% /description_term %}}
+{{% description_details %}}See [Authentication: [3dsecure]](#authentication-3dsecure-v2).
+{{% regex_optional %}}Optional{{% /regex_optional %}}
+{{% /description_details %}}
+{{% /description_list %}}
+
 #### Method: token[m4m]
 
 The required values are found in either the MDES `transact` response or the Secure Card on File (SCOF) `checkout` response.