🐛 Fix normalize {} to [] for slice defaults in CRDs

[kvaps]

What this fixes

Right now if you set a default with an inline object that contains a slice, and use {} as the value, the generator ends up treating it as an object instead of an empty list.

For example, if I use:

// +kubebuilder:default:={"md0":{"ephemeralStorage":"20Gi","gpus":{},"instanceType":"u1.medium","maxReplicas":10,"minReplicas":0,"resources":{},"roles":{"ingress-nginx"}}}

the generated CRD gives me:

default:
  md0:
    ephemeralStorage: 20Gi
    gpus: {}
    instanceType: u1.medium
    maxReplicas: 10
    minReplicas: 0
    resources: {}
    roles:
    - ingress-nginx

but since gpus is a slice, what I actually want (and what users would expect) is:

default:
  md0:
    ephemeralStorage: 20Gi
    gpus: []
    instanceType: u1.medium
    maxReplicas: 10
    minReplicas: 0
    resources: {}
    roles:
    - ingress-nginx

What changed

• Added a normalization step in ApplyToSchema that looks at the target schema type and coerces {} → [] when the field is an array (and vice versa for objects).
• This runs recursively, so nested defaults inside maps/objects are also fixed.
• Extended the testdata with cases for nested slices inside maps/objects to make sure the behavior is covered.

Why

It’s a small thing, but it avoids confusion when writing defaults for slices. Before this patch, the CRD schema would show gpus: {}, which is wrong and makes clients unhappy. Now it consistently produces [].

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