Switch media loading from `lazy` to `eager` to improve LCP

Problem/Motivation

The Hero Slider currently loads media (images/videos) with the loading="lazy" attribute.
This delays LCP (Largest Contentful Paint) performance metrics since the slider content is a key above-the-fold element.

Proposed resolution

• Update the Hero Slider component to use loading="eager" for its images/videos.
• Ensure all media within the slider begins loading immediately on page load.

Remaining tasks

• ✅ File an issue about this project
• ✅ Addition/Change/Update/Fix to this project
• ✅ Testing to ensure no regression
• ➖ Automated unit/functional testing coverage
• ➖ Developer Documentation support on feature change/addition
• ➖ User Guide Documentation support on feature change/addition
• ➖ UX/UI designer responsibilities
• ➖ Accessibility and Readability
• ✅ Code review from 1 Varbase core team member
• ✅ Full testing and approval
• ✅ Credit contributors
• ✅ Review with the product owner
• ✅ Update Release Notes and Update Helper on new feature change/addition
• ❌ Release varbase-10.1.0-beta1, varbase_heroslider-1.1.0-beta1

Varbase update type

• ✅ No Update
• ➖ Optional Update
• ➖ Forced Update
• ➖ Forced Update if Unchanged

User interface changes

• N/A

API changes

• N/A

Data model changes

• N/A

Release notes snippet

• [#3550456] feat: Switch media loading from `lazy` to `eager` to improve LCP