Invite people to a copyparty / birthday party / wedding: Easyily gather and share pictures & videos and have a live feed to display on a screen

NOTE:
**please use english, or include an english translation.** aside from that,
all of the below are optional, consider them as inspiration, delete and rewrite at will
**Use of English language ✅:** "Methinks these instructions hath scrambled mine wits—marry, I fain would see no mention of English niceties!"

**is your feature request related to a problem? Please describe.**

So... My real life problem is **sharing pictures and videos from an event** like a birthday party... or a particular part of a party for people to introduce copyparty.
_Picturing particular parts presenting a prior copyparty party. (say that 10 times but fast)_

And also **gathering media** from the event participants.
Nextcloud would be the tool but it is soooo slow, sluggish to set up and not mentioning the ux.

Also, It would be nice to have a display, like a Smart TV with a webbrowser, connected to copyparty.
The display shows a **slideshow**
- of incoming pictures and videos,
- The name of the party participant corresponding to the uploaded media
- including a customizable qr code on the bottom right for sharing and getting pictures.

Optionally, over the presentation qr code,
- users can setup an (temporary / self destructible) account _and/or_
- use the device finger print / a cookies / a temporary access code / their name to get recognized again for file operations accross devices.
-> This is for sending files meanwhile _and_ after the party on or delete the [drunken 🦆 pic](https://get.pxhere.com/photo/bird-cute-beak-hat-yellow-beer-duck-toys-vertebrate-funny-bavaria-waterfowl-water-bird-munich-oktoberfest-bath-duck-rubber-duck-squeak-duck-ducks-geese-and-swans-821755.jpg) you've send by mistake to copyparty. (thinking of that, a delay picturing newly added files in the presentation mode would be a nice feature)
- access the event folder and upload form for the media from the event

But wait, there is more!
The copyparty App runs in the background in the party mode, monitors media taken from the photo app folder and uploads it automatically (dangerous and funny) to the event folder. (Good for photographers, hosts of an event taking pictures, kids with the order to take pictures of the wedding as Arbeitsbeschaffungsmaßnahme,...)
Could be useful for a photobooth as well.

Something like sending notes to the presentation... un-/assigned to the media. That's a half-backed idea.

**Describe the idea / solution you'd like**
Introduce the copyparty party mode. 🎉
Easily gather, share and display media from an event.

**Describe any alternatives you've considered**
nextcloud, full sftp introduction presentation prior the party, dropbox alike services

该 issue 描述了一个用于媒体共享和实时显示的新功能“party mode”。首先探索 codebase 中现有的 media indexer 和 upload 功能。查找 WebDAV、SFTP 或 HTTP upload handler，以了解当前的文件操作。该功能需要 slideshow UI、QR code 生成，以及可能的后台应用上传，这些都是复杂的新增内容。

由索引模型根据 Issue 内容生成。