[fix] Nullable fields must have default values (#7522)

packages/twenty-server/src/engine/metadata-modules/field-metadata/field-metadata.service.ts

@@ -745,6 +745,15 @@ export class FieldMetadataService extends TypeOrmQueryService<FieldMetadataEntit
       }
     }
 
+    if (!fieldMetadataInput.isNullable) {
+      if (!fieldMetadataInput.defaultValue) {
+        throw new FieldMetadataException(
+          'Default value is required for non nullable fields',
+          FieldMetadataExceptionCode.INVALID_FIELD_INPUT,
+        );
+      }
+    }
+
     if (fieldMetadataInput.options) {
       for (const option of fieldMetadataInput.options) {
         if (exceedsDatabaseIdentifierMaximumLength(option.value)) {