Adding factuality to zammad system

we have zammad 4 system.
we need to add some new functionality to the system.

Code needs to be forked (privet) on GitHub.
1. Source needs to be provided in gith .
2. No 3rd party code.
3. Installation doc.
4. Out it will need to add the code on production server by themselves
5. Production server is identical to dev server.
6. Code needs to be understandable with comments and understandable parameters and function names.

code review will be done by our team.