Configure job environments per job in the instance (e.g. export, render and publish jobs)

[BigRoy]

Is there an existing issue for this?

• I have searched the existing issues.

Please describe the feature you have in mind and explain what the current shortcomings are?

Preferably we expose a simple way to set environment variables for each type of job that may live in an instance or context. Since #32 we now have farm job env vars configurable on the publish context and the instance data - but we may need more granular control targeting different jobs like "render", "export", "publish", etc.

How would you imagine the implementation of the feature?

Define an API that allows to abstract away "jobs" that we can manage (by name or id?) in isolation of each other.

E.g. see description here

Are there any labels you wish to add?

• I have added the relevant labels to the enhancement request.

Describe alternatives you've considered:

No response

Additional context:

Relates to ynput/ayon-core#876