Scheduled messages ("send later")

### Your use case

#### What would you like to do?

Schedule sending a message ("send later").

#### Why would you like to do it?

To not manually have to remember sending messages at the right time. If I'm able or schedule sending the message, I can write it when I think about it and have it arrive timely when it is relevant.

#### How would you like to achieve it?

The best version of this feature would be to send the message to the homeserver instantly and have the server deliver it according to the message's schedule. Having it be client side is very limiting, particularly because the client has to be active to be able to send.

### Have you considered any alternatives?

I think Telegram does it amazingly. This is what it looks like:

| Scheduling a message | Scheduled messages |
| --- | --- |
|   |  |

### Additional context

_No response_