Dynamic Upstream Zone Size Configuration

[mpstefan]

As a user of NGF who's environment is growing quickly
I want NGF to automatically calculate the correct zone size for my environment
So that I do not have to constantly recalculate and update that value manually myself
And so that I do not run at an increased risk of running out of memory with NGF.

Acceptance

• At runtime, NGF will recalculate the necessary upsteam zone size based on the number of upstreams when an upstream is added or removed.