fix(kcl): avoid full OXR cast to prevent conditions type error

[kaessert]

Summary

• Use partial cast pattern for OXR deserialization in cluster function: keep raw oxr and cast only spec.parameters to the typed model
• Prevents EvaluationError on status.conditions where the auto-generated KCL model expects a typed list but Crossplane passes a generic list at runtime

Details

The auto-generated KCL model types status.conditions as [SpecificConditionType], but Crossplane populates it as a generic JSON list at runtime. Full OXR casting (oxr = Type{**option("params").oxr}) includes this field, causing:

EvaluationError: conditions?: [TypedList] — expect [...], got list

The fix follows the proven pattern from configuration-azure-aks v0.16.0:

# Before (fails):
oxr = platformrefv1alpha1.Cluster{**option("params").oxr}

# After (works, preserves type safety on parameters):
oxr = option("params").oxr
_params = platformrefv1alpha1.Cluster.spec.parameters{**oxr.spec?.parameters}

Test plan

• up project build succeeds
• Deploy on Crossplane v2 control plane and verify XCluster reconciles without KCL errors