Organizer dashboard should show a preview of the event page customization on the same pagee

Currently when an organizer customizes their event page, the preview button sends them to a new URL, which then is not clear for the user how to go back to the edit page

This preview should be shown on the same page where the organizer performs the edit

Locate the organizer event-page customization entry point and the current preview button behavior, then trace where it navigates. Done means the event-page preview is shown on the customization page itself, without making it unclear how to return to editing.

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