a feature to browse and select from upload image

when inserting an image, there are only options to upload a *New* image.

If an image needs to re reference in multiple places, it has to be uploaded multiple times, which is not only inconvenient, but also a wast of disk space. It's worse if during *Edit*, the linked is changed accidentally the image is forever gone.

I am wishing for an image browser of uploaded files like [wikijs ](https://js.wiki/) or [bookstack ](https://www.bookstackapp.com/). It does not have to be implemented the same the way, the existing of such a feature is more important.

The issue names no files, tests, or entry points. Start by locating the image insertion and upload flow, then review the linked Wiki.js and BookStack examples for browser and reuse behavior. Done means users can browse previously uploaded images and select one for insertion without duplicate uploads or accidental loss.

Written by the indexing model from the issue text.