feat: add the ability to make email optional (#994)

backend/internal/utils/ptr_util.go

@@ -1,13 +1,16 @@
 package utils
 
+// Ptr returns a pointer to the given value.
 func Ptr[T any](v T) *T {
 	return &v
 }
 
-func PtrValueOrZero[T any](ptr *T) T {
-	if ptr == nil {
-		var zero T
-		return zero
+// PtrOrNil returns a pointer to v if v is not the zero value of its type,
+// otherwise it returns nil.
+func PtrOrNil[T comparable](v T) *T {
+	var zero T
+	if v == zero {
+		return nil
 	}
-	return *ptr
+	return &v
 }