Rename Pulumi stacks to match new org/project/stack structure convention

[feoh]

Description/Context

Pulumi is changing the way stacks are named by default as defined in the documentation.

Plan/Design

Stacks should be named in the format organizaation/project/stack.

This may be an opportunity for us to refactor, as well as write a reusable helper to resolve stack references - this would live here.

We should talk to Pulumi to determine whether we need to prioritize this in the mid or long term.

Potentially helpful link https://github.com/pulumi/pulumi/discussions/12958