refactor(referenceddata): drop unused delivery types

SubjectRef, DeliveryRequest, and DeliveryResult had no consumers — speculative
scaffolding in a package meant to be shared platform-wide. Remove them before
they ship as API surface no one calls.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: scotwells

internal/referenceddata/types.go

@@ -42,40 +42,6 @@ type ObjectRef struct {
 // collected from a workload template.
 type ReferencedSet []ObjectRef
 
-// SubjectRef identifies the end-user making the admission request. Used by the
-// SAR admission check to verify that the submitting user can read each
-// referenced object.
-type SubjectRef struct {
-	Username string
-	Groups   []string
-	UID      string
-}
-
-// DeliveryRequest carries everything the resolver needs to materialise companion
-// objects on the downstream (cell) namespace.
-type DeliveryRequest struct {
-	// Subject is the user identity used for admission authorisation.
-	Subject SubjectRef
-
-	// ReferencedObjects is the deduplicated set of ConfigMaps and Secrets to deliver.
-	ReferencedObjects ReferencedSet
-
-	// DownstreamNamespace is the namespace on the cell where companions will land
-	// (typically ns-{project-uid}).
-	DownstreamNamespace string
-}
-
-// DeliveryResult is returned by the resolver after materialising companions.
-type DeliveryResult struct {
-	// CompanionNames is the deterministic list of companion object names produced
-	// by CompanionName, sorted the same way as the expected-set annotation.
-	CompanionNames []string
-
-	// AllDelivered is true when every companion in CompanionNames was
-	// successfully written (created or updated) to the downstream.
-	AllDelivered bool
-}
-
 // ProjectConfigSecretReader reads ConfigMaps and Secrets from a project's
 // control plane. Implementations must classify errors as ErrSourceNotFound or
 // ErrSourceUnauthorized where appropriate.