Refactor upload component

[Fischaela]

Goal is to have one or multiple components that can handle media objects, like images, files and audios. They should be able to show a media property and make it interactable (e.g. audio files should be able to be played).

Maybe make multiple upload components or better media components:

1. image
2. file
3. audio

All should have inputs for events

• dropped
• deleted
• updated

All should show a preview of their media, wether it was just uploaded or had a media file by default.

[Letty]

for audio and image are also file checks included - mime types