Adoption of Namespaces with --adopt-existing-resources

[Racer159]

Is your feature request related to a problem? Please describe.

As Ezra I want to be able to adopt namespaces with --adopt-existing-resources so that I can get deployments into a consistent state if the namespace already exists.

Describe the solution you'd like

• Given I have a Zarf package that deploys to a namespace
• And I do not override namespace labels in the Zarf package (i.e. with a namespace Helm template)
• And the namespace exists and has a zarf.dev/agent: ignore label
• When I deploy my package with --adopt-existing-resources
• Then the zarf.dev/agent: ignore label is dropped

---

• Given I have a Zarf package that deploys to a namespace
• And I have a zarf.dev/agent: ignore label in the Zarf package (i.e. with a namespace Helm template)
• And the namespace exists and has a zarf.dev/agent: ignore label
• When I deploy my package with --adopt-existing-resources
• Then the zarf.dev/agent: ignore label is kept

---

• Given I have a Zarf package that deploys to a namespace
• And I have a zarf.dev/agent: ignore label in the Zarf package (i.e. with a namespace Helm template)
• And the namespace exists and does not have additional labels
• When I deploy my package with --adopt-existing-resources
• Then the zarf.dev/agent: ignore label is added

Describe alternatives you've considered

This could be done with more labels or in a more global way but the zarf.dev/agent: ignore label is the most common Zarf-specific one folks may run into (especially given Zarf adds this label to all namespaces on zarf init).

Additional context

This came out of the resolution of: #2623

Namespace labels should not be mutate when not passing the --adopt-existing-resources flag

[phillebaba]

Relates to #2693