Implement forwarding of multiple messages at a time.

#### Is your suggestion related to a problem? Please describe.
As of right now, element lacks a means to select and forward a bunch of messages (contiguous or not).
Rather, one must manually select and forward to the target room each message individually, one by one.

#### Describe the solution you'd like.
It would be good if contiguous messages could be selected (via SHIFT for example),
or non-contiguous ones (via CTRL),
and then when clicking forward under the options message, all selected messages will be forwarded to selected target room.

#### Describe alternatives you've considered.

#### Additional context
I have been told that bulk forwarding options like this have been steered away from in the past as to not facilitate spamming and bulk posting of E2EE conversations to other rooms.
However, as there are currently no rate limiting mechanisms in place and spam is dealt with at the room moderation level, this concern in mainly an "accidental spam" one.

To prevent posting to a wrong room by mistake, we could use a dialog box which reads something along the lines of:
"You have selected messages from "
Please select target room from list, to forward:

"

I feel perhaps selecting the target room from a dropdown/scroll list in the dialog box is safer/more convenient than selecting the target room in the left panel of element, as that is usually used for navigation, and could lead to accidental clicks and brainfarts.

#### Related issues:
#14690
#5641