feat: Add configurable frame id prefix

[philipp-caspers]

In order to be able to properly handle (e.g. visualize) a multi robot scenario (where multiple voraus.core instances and bridges are running), one need the ability to distinguish between the coordinate systems of the different robots.
This change introduces an environment variable (FRAME_ID_PREFIX) to solve that problem.
The default value defined in the compose file is robot1, meaning that for example for the base_link coordinate system, the resulting frame_id is now: robot1_base_link.

[AguilaTaco]

As I am not a rust expert, my review might not be that helpful. But I spend quite a lot of time trying to understand it line to line and what I could unterstand looks good

[AiyionPrime]

I have not had time to look into this, just wanted to leave this here for now:
Whether someone is proficient in a specific field does IMO not influence the usefulness of PRs greatly. Either the code author or the reviewer learns something, ideally both.

Asking questions in PRs is a great way to have the answers to them near the relevant context and can be of great use to others a few weeks/months/years down the road.
Do never hesitate to ask.