This PR introduces an enhancement to the site's image-loading strategy
by implementing lazy loading as the default behavior for all images. The
motivation behind this change is to improve the site's load times.
**Changes:**
1. **Default Lazy Loading:** By `default`, all images will now have the
`loading="lazy"` attribute.
2. **Configurable Option in `_config.yml`:** Added a new configuration
option under `lazy_loading_images.enable`.
3. **Override Capability:** For `specific images` where the user doesn't
want lazy loading, they can `override` this by directly setting the
`loading attribute` in the `image tag`.
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