Exercises Engine Fixes

In this update I've focused on fixing issues with ad blockers and improving the mobile experience for exercises engine.

The exercises engine now detects when an ad blocker is active and displays helpful information about potential issues. Ad blockers can break some exercises that use the YouTube player, so this detection helps you understand why certain exercises might not work properly.

I've also added detection for when the YouTube player fails to start, along with a button to force reload it. This helps resolve playback issues sometimes, but it's best to just disable the ad blocker. You can see the issue in the video below.

I fixed issues with using exercises on small screens. Previously, it was sometimes impossible to scroll down and access all the buttons on mobile devices. This has been resolved, making exercises fully usable on phones and tablets.