Push notifications for specific user / group of users

**Have you read the documentation?**
- [x] Yes, but it does not include related information regarding my question.
- [ ] Yes, but the steps described in the documentation do not work on my machine.
- [ ] Yes, but I am having difficulty understanding it and wants clarification.

**You are setting up gotify in**
- [x] Docker
- [ ] Linux native platform
- [ ] Windows native platform

**Describe your problem**

Hi Team,

At the outset, thanks to the author(s) and all the contributors for this fantastic project. For one of my requirements I was considering Gotify. I have tested the project and have a fair amount of understanding on how it works; but wanted to get some of my queries clarified by the experts here.

I am developing a server side application which needs to send in-app push notifications to both web and mobile clients. Basically clients maintain a persistent WebSocket connection and server sends the notifications. For a send to all and receive by all (connected) clients, I can use Gotify as is. My requirement also include sending targeted message to specific user and group of users. I am wondering if this can be achieved through Gotify. I have explored the plugin (https://github.com/eternal-flame-AD/gotify-broadcast) which does a good job at broadcast in a channel and it probably solves my _send to a group_ use case. However it needs a lot of configuration and with more number of groups its going to be really complicated.

I am looking for suggestions from the Gotify community if anybody has solved similar use cases through Gotify. Any help/pointers will be highly appreciated. Thanks in advance.