Fix race condition bug where activating multiple features sequentially could fail to activate some features

[b1ink0]

Summary

Fixes #1660

Relevant technical choices

Implemented a queue based approach for activation of features / plugins using the AJAX in JavaScript.

Now only one features / plugin sends a request at a time other request are processed after previous request is finished.

Demo

demo-2.mp4

[github-actions]

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Co-authored-by: b1ink0 <b1ink0@git.wordpress.org>
Co-authored-by: mukeshpanchal27 <mukesh27@git.wordpress.org>
Co-authored-by: westonruter <westonruter@git.wordpress.org>
Co-authored-by: felixarntz <flixos90@git.wordpress.org>

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[mukeshpanchal27]

Thanks @b1ink0 for the PR.

When plugins are activated simultaneously, while some plugins in the waiting state reloading the settings page. After the reload, some plugins display the Activate button again, even though they are already installed and activated, while others remain unactivated.

This is not a blocker but something I observed during testing.

Screen.Recording.2024-11-19.at.5.11.14.PM.mov

[b1ink0]

When plugins are activated simultaneously, while some plugins in the waiting state reloading the settings page. After the reload, some plugins display the Activate button again, even though they are already installed and activated, while others remain unactivated.

@mukeshpanchal27
I believe this is happening because when the plugin is in the Activating... state, the request to activate the plugin is sent. If you reload quickly, it will show Activate because the request to activate the plugin is not finished. This means the plugin is not activated yet, which correctly reflects on the Performance Features page. Then, when you later go to the plugins page, it shows the plugins as activated because the request to activate the plugin has now finished.

demo-3.mp4

[westonruter]

LGTM

[felixarntz]

FYI I've changed the base branch to a new release/3.6.1, since this should go into a hot fix release for purely this fix.

[felixarntz]

@b1ink0 This looks great, thank you for the fix and fast turnaround time!

Not a blocker