[WIP] Fix featured image disappearing after saving post from Optimole DAM

[Copilot]

Thanks for assigning this issue to me. I'm starting to work on it and will keep this PR's description up to date as I form a plan and make progress.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Featured image disappears after saving post when selected from Optimole DAM</issue_title>
<issue_description>### Description:
When setting a featured image using an image imported via Optimole DAM, the image is correctly selected and displayed initially. However, after saving or updating the post, the featured image automatically disappears.

This issue occurs consistently and prevents users from using Optimole DAM images as featured images.

Steps to Reproduce:

1. Go to Posts → Add New (or edit an existing post).
2. Click Set Featured Image.
3. Select an image imported via Optimole DAM.
4. Confirm the image is set as the featured image.
5. Click Save Draft, Publish, or Update.
6. After the page reloads, observe that the featured image is no longer set.

Reported here - https://secure.helpscout.net/conversation/3240818826/484051</issue_description>

<agent_instructions>Fix the reported issue. Create a new pr for this ensure all wordpress coding guidelines are followed and the fix dont introduce any regressions
</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Featured image disappears after saving post when selected from Optimole DAM #1025

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