MQTT: Support wildcards in topic filters matching retained messages

[getlarge]

See description and conversation in rabbitmq#13048

[robertsLando]

when I delete a retained message I see a publish of {} instead. After this if I disconnect and re-connect I don't see it anymore so it's partially working.

Screencast.da.2025-02-12.10-50-09.webm

[mortdiggiddy]

Hello there Mr. getLarge.

I have followed your work regarding this ticket and all of the progress you made, right up until the point where it would not be accepted by the RabbitMQ team :)

We are very interested in a feature like this, I work in a Robotics Lab in Dubai. I ran into this issue the other day trying to understand why retained topics with a '+' for word replacement was not working when the retain flag is set by the publisher.

I have thoroughly reviewed the entire history of this request, all the way back to July 2018 where it seems to have started.

How can my team use your work and adopt this (Earlang plugin?) into our running RabbitMQ single instance as well as our 3.13 instances running inside the Rabbit MQ cluster operator on Kubernetes.

I am willing to help write any code to make this happen.

@getlarge @robertsLando