[Bug] GLightbox functionality is not working for documentation images

Description

While browsing the WSO2 Devant Documentation, I noticed that the GLightbox feature for enlarging images is currently not functioning as expected. Clicking on images does not trigger the lightbox overlay.

As a result, users are unable to view images in an enlarged format without opening them separately.

Steps to Reproduce

1. Navigate to any documentation page that contains an image.
2. Click on the image.
3. Observe that the GLightbox overlay does not open.

Expected Behavior

Clicking on an image should open it in a GLightbox overlay, allowing users to view the image in full screen or higher resolution without leaving the page.

Proposed Fix

I have previously encountered and resolved a similar issue in the WSO2 API Manager documentation repository.
I will apply a similar fix here by ensuring the required GLightbox CSS and JavaScript dependencies are properly included and initialized.

Contribution

I will work on fixing this issue and submit a Pull Request with the necessary changes.

Start by reproducing the issue on a WSO2 Devant Documentation page containing an image, then inspect where GLightbox CSS and JavaScript dependencies are included and initialized. Done means clicking a documentation image opens the GLightbox overlay without leaving the page.