Use signal-cli to clone messages with attachments from one group to another

[etwasch]

We have a signal group in Switzerland for punk concerts (kønzi). It reached the limit of 1000 members.
The idea was for a simple signal bot that copies every new message in kønzi to another group (kønzi2).

If somebody finds this discussion, here is the script I crudely ape coded in bash:
https://github.com/etwasch/signal-forwarder-bot