Introduce ARRAY field type (#6862)

This PR was created by \[GitStart\](<https://gitstart.com/>) to address
the requirements from this ticket:
\[TWNTY-6447\](<https://clients.gitstart.com/twenty/5449/tickets/TWNTY-6447>).

This ticket was imported from:
<https://github.com/twentyhq/twenty/issues/6447>

### Description

\- We added a new field type

### Refs

#6447

### Demo

<https://jam.dev/c/2b4d7853-ea89-4e9d-a561-6edcb4fdb34b>

Fixes #6447

---------

Co-authored-by: gitstart-twenty <gitstart-twenty@users.noreply.github.com>
Co-authored-by: Charles Bochet <charles@twenty.com>

packages/twenty-server/src/engine/api/__mocks__/object-metadata-item.mock.ts

@@ -230,6 +230,13 @@ const fieldEmailsMock = {
   defaultValue: [{ primaryEmail: '', additionalEmails: {} }],
 };
 
+const fieldArrayMock = {
+  name: 'fieldArray',
+  type: FieldMetadataType.ARRAY,
+  isNullable: true,
+  defaultValue: null,
+};
+
 const fieldPhonesMock = {
   name: FIELD_PHONES_MOCK_NAME,
   type: FieldMetadataType.PHONES,
@@ -267,6 +274,7 @@ export const fields = [
   fieldRawJsonMock,
   fieldRichTextMock,
   fieldActorMock,
+  fieldArrayMock,
 ];
 
 export const objectMetadataItemMock = {