Load pages from pager within active modal

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Rebased onto an MR and added additional tests.

So using views_test_modal module from core
When I click the link (which has class use-ajax)
Modal opens
Clicking a page items renders some errors

Applying the patch

I get the same results.

Using content view with ajax turned off ( as the issue summary didn't mention turning it on)

Posted review on the MR

Rebased onto 11.x and changed target. There was a conflict with 10.1.x that needed resolving first. Thanks to @larowlan for helping with the git foo.

Using only this condition:
\Drupal::request()->get(MainContentViewSubscriber::WRAPPER_FORMAT) === 'drupal_modal'
seems to fail in some use cases.
I have a modal form with ajax submit and tableselect element with pager. Applying this patch, pager links get ajaxified and work well until a validation error occurs. During submit, request wrapper format is "drupal_ajax", so after validation fails condition does not pass and links don't have use-ajax class and data attributes anymore.
Adding this:
in_array(\Drupal::request()->get(MainContentViewSubscriber::WRAPPER_FORMAT), ['drupal_ajax', 'drupal_modal'])
make pager work also after a failed validation, but i don't know if this can have unwanted side effects.

Tested with Drupal 10.2.6, it works well with pager inside modal and without views. I use pager render array like this :

[
        '#type' => 'pager',
        '#route_name' => '<current>',
]

Rebased and resolved the conflicts.

Ready for another review.

Left some comments in the MR.

Feedback addressed, I tried to find why we were using olivero and I think it was mainly to demonstrate the fix works there but I think Stark makes more sense.

Drupal\Tests\file\Functional\DownloadTest pretty sure unrelated.

Rest of the feedback appears to be addressed.

+1 RTBC, works fine when the modal has a pager.

The Needs Review Queue Bot → tested this issue. It no longer applies to Drupal core. Therefore, this issue status is now "Needs work".

This does not mean that the patch necessarily needs to be re-rolled or the MR rebased. Read the Issue Summary, the issue tags and the latest discussion here to determine what needs to be done.

Consult the Drupal Contributor Guide → to find step-by-step guides for working with issues.