feat: Add immersive full-screen preview for images and videos with swipe/arrow navigation

Currently, when viewing media content (images and videos) within the app, there is no dedicated immersive full-screen preview mode. It can be inconvenient to open each media file individually and close it before moving to the next one, especially when an article or feed contains multiple media assets.

I would like to suggest adding an immersive full-screen preview feature for both images and videos. Key capabilities should include:

Full-screen/Immersive View: Click on an image or video to open it in a clean, distraction-free full-screen overlay.

Smooth Navigation: Support switching between the media contents (images and videos) seamlessly by scrolling up/down (or using keyboard Arrow Up/Down keys / swipe gestures).

Opening each image/video in an external browser or media player, which disrupts the reading flow within the app.

This would greatly enhance the user experience for media-heavy feeds, making content consumption much more fluid and engaging.