refactor: remove empty services (#116)

* remove empty services

* remove old factory

* remove old static files

* cleanup more duplicate service code

* file/folder reorg

backend/internal/data/repo/id_set.go

@@ -0,0 +1,21 @@
+package repo
+
+import (
+	"github.com/google/uuid"
+	"github.com/hay-kot/homebox/backend/pkgs/set"
+)
+
+// HasID is an interface to entities that have an ID uuid.UUID field and a GetID() method.
+// This interface is fulfilled by all entities generated by entgo.io/ent via a custom template
+type HasID interface {
+	GetID() uuid.UUID
+}
+
+func newIDSet[T HasID](entities []T) set.Set[uuid.UUID] {
+	uuids := make([]uuid.UUID, 0, len(entities))
+	for _, e := range entities {
+		uuids = append(uuids, e.GetID())
+	}
+
+	return set.New(uuids...)
+}