fix: Allow optional email values in custom fields

test/membership/custom_field_validation_test.exs

@@ -1,7 +1,7 @@
 defmodule Mv.Membership.CustomFieldValidationTest do
   @moduledoc """
   Tests for CustomField validation constraints.
-  
+
   Tests cover:
   - Name length validation (max 100 characters)
   - Name trimming
@@ -203,4 +203,3 @@ defmodule Mv.Membership.CustomFieldValidationTest do
     end
   end
 end
-

test/membership/custom_field_value_validation_test.exs

@@ -1,7 +1,7 @@
 defmodule Mv.Membership.CustomFieldValueValidationTest do
   @moduledoc """
   Tests for CustomFieldValue validation constraints.
-  
+
   Tests cover:
   - String value length validation (max 10,000 characters)
   - String value trimming
@@ -184,6 +184,36 @@ defmodule Mv.Membership.CustomFieldValueValidationTest do
   end
 
   describe "email value validation" do
+    test "accepts nil value (optional field)", %{member: member, email_field: email_field} do
+      assert {:ok, custom_field_value} =
+               CustomFieldValue
+               |> Ash.Changeset.for_create(:create, %{
+                 member_id: member.id,
+                 custom_field_id: email_field.id,
+                 value: %{"_union_type" => "email", "_union_value" => nil}
+               })
+               |> Ash.create()
+
+      assert custom_field_value.value.value == nil
+    end
+
+    test "accepts empty string (becomes nil after trim)", %{
+      member: member,
+      email_field: email_field
+    } do
+      assert {:ok, custom_field_value} =
+               CustomFieldValue
+               |> Ash.Changeset.for_create(:create, %{
+                 member_id: member.id,
+                 custom_field_id: email_field.id,
+                 value: %{"_union_type" => "email", "_union_value" => ""}
+               })
+               |> Ash.create()
+
+      # Empty string after trim should become nil
+      assert custom_field_value.value.value == nil
+    end
+
     test "accepts valid email", %{member: member, email_field: email_field} do
       assert {:ok, custom_field_value} =
                CustomFieldValue
@@ -273,4 +303,3 @@ defmodule Mv.Membership.CustomFieldValueValidationTest do
     end
   end
 end
-