Allow mounting additional directories and environment variables to Helm chart

[DiamondJoseph]

This would be to e.g. mount configuration for detectors.
This should probably be in the form of allowing the definition of additional configmaps to mount to the pod.

Acceptance Criteria

• Specific criteria that will be used to judge if the issue is fixed

[DominicOram]

FYI @noemifrisina we also need this in MX + Crystallography to mount lookup tables. Though the more permanent service that @Relm-Arrowny is working on would help this.

[callumforrester]

So I think it's important to say from the top that we're reluctant to introduce dependencies on /dls_sw that we then have to get rid of later. I'm more comfortable with it now that we have a solid plan to replace them. On the other hand it might be a better use of the core team's time to help @Relm-Arrowny.

@DominicOram @noemifrisina and @olliesilvester please could you provide more details on how much this is blocking you?

[Relm-Arrowny]

I am just on the starting block on this, here is what I am planing to do if it make any sense.

[noemifrisina]

At the moment, the main issue for me is that devices relying on lookup tables - which live in /dls_sw/ - can't connect on the blueapi running on the beamline cluster. For the moment there's more work to do first on the i19 side, so it's not blocking much, it may become more problematic as devices and plans are added.

@Relm-Arrowny Just so I'm caught up, what is the service you're working on?

[olliesilvester]

I'm likely to run into this in the next 6 weeks, but would be happy to help with @Relm-Arrowny 's service rather than do a temporary solution

[Relm-Arrowny]

@Relm-Arrowny Just so I'm caught up, what is the service you're working on?

I am planing to do something similar to this https://github.com/DiamondLightSource/daq-config-server. I have not really got started other than look into what I need to do, so that it will work with supergraph