Add JSON field type and Event object (#4566)

* Add JSON field type and Event object

* Simplify code

* Adress PR comments and add featureFlag

packages/twenty-server/src/database/typeorm-seeds/core/feature-flags.ts

@@ -25,6 +25,11 @@ export const seedFeatureFlags = async (
         workspaceId: workspaceId,
         value: true,
       },
+      {
+        key: FeatureFlagKeys.IsEventObjectEnabled,
+        workspaceId: workspaceId,
+        value: true,
+      },
     ])
     .execute();
 };