Add Lazy Loading and Thumbnails to Events Page Images

[0xquark]

Closes #88
Each original high quality image is roughly 5 MB in size, which caused the page to lag when loading them all at once. To address this, I implemented lazy loading and added optimized thumbnails that display while the full-resolution images load in the background. With lazy loading, images now load only as users scroll through the page. This approach allows us to retain the quality of images without compromising performance or loading times.
I replaced all the previously blurry images with better quality ratio thumbnails, while retaining the original for lazy loading.