Consistently apply secrets & image mutations

[RothAndrew]

As a user of Zarf I want the ability to write up my manifests/charts/kustomizations without needing to spend a lot of time modifying them to use Zarf's internal registry instead of the upstream registry, so that I can more easily use existing configurations without having to change them.

Example: My deployment specifies Docker Hub and registry1.dso.mil for all my image paths, which would completely break in an airgap since those locations are not reachable.

Notes:

• We want to do this in a way that minimizes "magical" behavior. Doing this consistently one way across the entire cluster helps us easily explain what is happening
• Keep in mind that the Zarf registry requires an imagePullSecret since it hosts its images behind authn/authz

Acceptance Criteria:

• The Kubernetes Mutating Webhook pattern is used to accomplish this outcome of automatically changing all image definitions such that the Zarf registry is used instead of the upstream registry.
• By default, the cluster automatically mutates ALL image definitions
• I can override the behavior and have individual image definitions not be mutated by applying some label/annotation/flag