vaani : refactor: Optimize image loading logic and update dependencies

This commit optimizes the image loading logic in the App.vue, HomeView.vue, and posts.vue components. It simplifies the code by removing unnecessary div elements and improves the rendering of images. The changes also include fixing a bug where images were not displayed correctly when the attachment type was 'image'. Additionally, the dependencies "@helia/unixfs" and "helia" have been updated to their latest stable versions. These improvements enhance the page load performance and provide a better user experience.

https://github.com/besoeasy/vaani/commit/f6826f6669c0707f3534e8c1127c3460610c9443