[Blaze] Fix campaign creation when products use a PDF file thumbnail as image

[hichamboushaba]

Closes WOOMOB-1348

Description

This PR fixes an issue where the app could send a PDF URL in the main_image.url field when creating a campaign, and main_image.mime_type set to application/pdf.

For more information on how this happens, check out the details here: pe5sF9-4CI-p2. In short, the product image is set to a thumbnail of a PDF file uploaded to the store, and the app uses the PDF URL and not the thumbnail URL, this was caused by the fact that we fetch the Media object to get its mime type, resulting in using a different URL. To fix this, this PR updates the logic to infer the MIME type when fetching image dimensions, so we no longer need to fetch the Media object. This also optimizes the campaign creation process by eliminating one API request.

To explain this more, for the test store that we'll use for reproducing the issue, the details are shown below:

Product details:

{
  "id": 62,
  "name": "PDF Image Product",
  "slug": "pdf-image-product",
  "permalink": "https:\/\/fortunately-square.jurassic.ninja\/product\/pdf-image-product\/",
  "images": [
    {
      "id": 61,
      "date_created": "2025-09-19T15:12:06",
      "date_created_gmt": "2025-09-19T15:12:06",
      "date_modified": "2025-09-19T15:12:06",
      "date_modified_gmt": "2025-09-19T15:12:06",
      "src": "https:\/\/fortunately-square.jurassic.ninja\/wp-content\/uploads\/2025\/09\/pdf-61-full.jpg",
      "name": "sample",
      "alt": ""
    }
  ],
  ...
}

Blaze campaign creation request before

{
  "origin": "wc-android",
  "origin_version": "23.2",
  "target_urn": "urn:wpcom:post:248546480:62",
  "type": "product",
  "payment_method_id": "PW-15849315",
  "start_date": "2025-09-19",
  "end_date": "2025-09-26",
  "time_zone": "Africa/Casablanca",
  "budget": {
    "mode": "daily",
    "amount": 5.0,
    "currency": "USD"
  },
  "site_name": "Transform Your PDFs!",
  "text_snippet": "Unlock the power of PDF images like never before. Explore now!",
  "cta_text": "Discover More",
  "target_url": "https://fortunately-square.jurassic.ninja/product/pdf-image-product/",
  "url_params": "",
  "main_image": {
    "url": "https://fortunately-square.jurassic.ninja/wp-content/uploads/2025/09/sample.pdf",
    "mime_type": "application/pdf"
  },
  "targeting": {
    "locations": [],
    "languages": [],
    "devices": [],
    "page_topics": []
  },
  "is_evergreen": true,
  "objective": "sales",
  "accepted_tos": true
}

Blaze campaign creation request after the fix

{
  "origin": "wc-android",
  "origin_version": "23.2",
  "target_urn": "urn:wpcom:post:248546480:62",
  "type": "product",
  "payment_method_id": "PW-15849315",
  "start_date": "2025-09-19",
  "end_date": "2025-09-26",
  "time_zone": "Africa/Casablanca",
  "budget": {
    "mode": "daily",
    "amount": 5.0,
    "currency": "USD"
  },
  "site_name": "Transform Your PDFs!",
  "text_snippet": "Unlock the power of PDF images like never before. Explore now!",
  "cta_text": "Discover More",
  "target_url": "https://fortunately-square.jurassic.ninja/product/pdf-image-product/",
  "url_params": "",
  "main_image": {
    "url": "https://fortunately-square.jurassic.ninja/wp-content/uploads/2025/09/pdf-61-full.jpg",
    "mime_type": "image/jpeg"
  },
  "targeting": {
    "locations": [],
    "languages": [],
    "devices": [],
    "page_topics": []
  },
  "is_evergreen": true,
  "objective": "sales",
  "accepted_tos": true
}

Steps to reproduce

1. Creating a website with the issue is not a straightforward process, so ping me in a DM to share a test store.
2. Open the app.
3. Create a Blaze campaign using the default AD image.

Testing information

• Confirm the PR fixes the issue.

The tests that have been performed

The above.

• I have considered if this change warrants release notes and have added them to RELEASE-NOTES.txt if necessary. Use the "[Internal]" label for non-user-facing changes.

[wpmobilebot]

📲 You can test the changes from this Pull Request in WooCommerce-Wear Android by scanning the QR code below to install the corresponding build.

	App Name	WooCommerce-Wear Android
	Platform	⌚️ Wear OS
	Flavor	Jalapeno
	Build Type	Debug
	Commit	91fa844
	Direct Download	woocommerce-wear-prototype-build-pr14642-91fa844.apk

[wpmobilebot]

📲 You can test the changes from this Pull Request in WooCommerce Android by scanning the QR code below to install the corresponding build.

	App Name	WooCommerce Android
	Platform	📱 Mobile
	Flavor	Jalapeno
	Build Type	Debug
	Commit	91fa844
	Direct Download	woocommerce-prototype-build-pr14642-91fa844.apk

[AdamGrzybkowski]

Tested with trunk to reproduce first and then confirmed the campaign creation works with this PR ✅

Any reason you haven't added a milestone?

[hichamboushaba]

Any reason you haven't added a milestone?

Thanks for the review @AdamGrzybkowski, I just missed it 🙂