What's New post for User Journeys

[ssimpson-newrelic]

This is a long overdue post for the Browser User Journeys feature that went GA on 2025-09-26

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[github-actions]

Hi @ssimpson-newrelic 👋

Thanks for your pull request! Your PR is in a queue, and a writer will take a look soon. We generally publish small edits within one business day, and larger edits within three days.

Please ensure the propsed changes look good by building it first in your local environment. Refer to this contribution guide to get the site up and running in your local.

If you really require a preview url, reach out to one of the writers and they will generate one for you.

[adutta-newrelic]

Hello @ssimpson-newrelic could you please sign the CLA so that we can go ahead and review the PR

[adutta-newrelic]

LGTM