Add Instance log passthrough support

[hardillb]

part of #3324

Description

Allow nr-launcher to print Node-RED logs (in JSON format) to stdout. This allows it to be ingested by log services on docker/k8s

Related Issue(s)

#3324

Checklist

• I have read the contribution guidelines
• Suitable unit/system level tests have been added and they pass
• Documentation has been updated
  • Upgrade instructions
  • Configuration details
  • Concepts
• Changes flowforge.yml?
  • Issue/PR raised on FlowFuse/helm to update ConfigMap Template
  • Issue/PR raised on FlowFuse/CloudProject to update values for Staging/Production

Labels

• Backport needed? -> add the backport label
• Includes a DB migration? -> add the area:migration label

[hardillb]

Pairs with FlowFuse/nr-launcher#207

[knolleary]

My concern is what a FF Cloud user will think this option does - as it will do nothing for them. And there needs to be some documentation somewhere on what this feature does.

Does this really need to be on a per-instance basis or can it be an option set via the yml file?

[hardillb]

It could be done as a env var injected into the container by the driver. I'll give it a rework

[hardillb]

Move to driver level configuration

FlowFuse/driver-k8s#136
FlowFuse/driver-docker#82
FlowFuse/driver-localfs#114

FlowFuse/helm#300