Feature request: support for Stories (MSC3588)

[Mikaela]

Is your feature request related to a problem? Please describe.

Currently stories appear as read-only rooms in Element Web and Element Android (entirely invisible in Element iOS, element-hq/element-ios#5455).

Describe the solution you'd like

I would like stories to be implemented according to the MSC, matrix-org/matrix-spec-proposals#3588

Describe alternatives you've considered

They could be left as read-only rooms as long as Element iOS got fixed (element-hq/element-ios#5455)

Additional context

Stories were implemented in FluffyChat 1.2.0 released a couple of days ago so more Element users may be seeing stories rooms and wonder what they are about. They are also supported by minesTrix.

[Mikaela]

In Element Web it would be nice to at least be able to see the story text with image uploads without having to open event source for that,

{
  "content": {
    "msgtype": "m.image",
    "body": "Who am I to oppose the magic 8ball?",
...
    }
}