chore(POCP-914): Add authenticate_only to request payload

[lukasz-k-bieszczad-cko]

Description

Po.js needs to handle new flow for authenticate only.

Solution

Allow passing authenticate_only param in options for handleCardActions

Checklist

• I bumped the version of the project using yarn bump-version
• I have checked the code for any potential issues
• I tested my changes in the browser

Notes

https://checkout.atlassian.net/wiki/spaces/POUT/pages/7372308491/2025-09-23+Separating+authentication+3DS+from+authorization+flow#PO.js-and-Dashboard-Changes

Jira Issue

https://checkout.atlassian.net/browse/POCP-914

[Copilot]

Pull Request Overview

This PR adds support for an authenticate_only parameter to handle a new authentication-only flow in the payment processing system, allowing authentication to be separated from authorization.

• Added authenticate_only parameter to the request payload in handleCardActions
• Bumped package version from 1.5.0 to 1.5.1

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/processout/processout.ts	Added authenticate_only field to the payload object to support authentication-only flow
package.json	Version bump from 1.5.0 to 1.5.1

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