[REQUIRES_FULL_CACHE_FLUSH_WHEN_RELEASED] Refactor FlatEntity to be UniversalFlatEntity superset (#17452)

# Introduction
In this PR we're refactoring the `FlatEntity` type to become a superset
of the `UniversalFlatEntity`.
Right now we're storing all the extra properties in `__universal`
property, at some point it might just be sibling to other entity and we
might rely on the `propertiesToCompare` constants and TypeScript
allowing passing a superset type into a smaller subset type

## FromTo utils
The entity to flat entity method now computes the universal information,
standardized a typing and pattern to do

## Example
Also strictly type
```ts
    "bbb019ea-6205-498c-aea5-67bc53bce8a9": {
      "workspaceId": "20202020-1c25-4d02-bf25-6aeccf7ea419",
      "universalIdentifier": "20202020-d111-4d11-8d11-da5ab0a11002",
      "applicationId": "d01b010d-b984-465b-b40b-370e954e5188",
      "id": "bbb019ea-6205-498c-aea5-67bc53bce8a9",
      "pageLayoutTabId": "791a512f-169f-4209-b731-aa86716668c6",
      "title": "Deals by Company",
      "type": "GRAPH",
      "objectMetadataId": "9e14efea-df5b-4c0e-aba9-cfe455f32397",
      "gridPosition": { "row": 0, "column": 6, "rowSpan": 6, "columnSpan": 6 },
      "configuration": {
        "color": "orange",
        "orderBy": "FIELD_ASC",
        "timezone": "UTC",
        "displayLegend": true,
        "displayDataLabel": false,
        "showCenterMetric": true,
        "configurationType": "PIE_CHART",
        "firstDayOfTheWeek": 0,
        "aggregateOperation": "COUNT",
        "groupBySubFieldName": "name",
        "groupByFieldMetadataId": "6673ff18-63d2-47a1-8f85-2b9b09ca27a5",
        "aggregateFieldMetadataId": "8d64ee41-5dd4-4de6-945a-7c0c18399715"
      },
      "createdAt": "2026-01-28T14:08:52.140Z",
      "updatedAt": "2026-01-28T14:08:52.140Z",
      "deletedAt": null,
      "__universal": {
        "universalIdentifier": "20202020-d111-4d11-8d11-da5ab0a11002",
        "applicationUniversalIdentifier": "20202020-64aa-4b6f-b003-9c74b97cee20",
        "pageLayoutTabUniversalIdentifier": "20202020-d011-4d11-8d11-da5ab0a01001",
        "objectMetadataUniversalIdentifier": "20202020-9549-49dd-b2b2-883999db8938",
        "gridPosition": {
          "row": 0,
          "column": 6,
          "rowSpan": 6,
          "columnSpan": 6
        },
        "configuration": {
          "color": "orange",
          "orderBy": "FIELD_ASC",
          "timezone": "UTC",
          "displayLegend": true,
          "displayDataLabel": false,
          "showCenterMetric": true,
          "configurationType": "PIE_CHART",
          "firstDayOfTheWeek": 0,
          "aggregateOperation": "COUNT",
          "groupBySubFieldName": "name",
          "aggregateFieldMetadataUniversalIdentifier": "20202020-d01a-4131-8a31-f123456789ab",
          "groupByFieldMetadataUniversalIdentifier": "20202020-cbac-457e-b565-adece5fc815f"
        }
      }
    },
```

packages/twenty-shared/src/types/ExtractSerializedRelationProperties.type.ts

@@ -1,14 +1,11 @@
-import { type SERIALIZED_RELATION_BRAND } from './SerializedRelation.type';
-
-type HasSerializedRelationPropertyBrand<T> =
-  typeof SERIALIZED_RELATION_BRAND extends keyof T ? true : false;
+import { IsSerializedRelation } from "@/types/IsSerializedRelation.type";
 
 export type ExtractSerializedRelationProperties<T> = T extends unknown
   ? T extends object
     ? {
         [P in keyof T]-?: [NonNullable<T[P]>] extends [never]
           ? never
-          : HasSerializedRelationPropertyBrand<NonNullable<T[P]>> extends true
+          : IsSerializedRelation<NonNullable<T[P]>> extends true
             ? P
             : never;
       }[keyof T]

packages/twenty-shared/src/types/IsSerializedRelation.type.ts

@@ -0,0 +1,4 @@
+import { SERIALIZED_RELATION_BRAND } from '@/types/SerializedRelation.type';
+
+export type IsSerializedRelation<T> =
+  typeof SERIALIZED_RELATION_BRAND extends keyof T ? true : false;

packages/twenty-shared/src/types/__tests__/extract-serialized-relation-properties.type-test.ts

@@ -66,4 +66,20 @@ type Assertions = [
       'rel'
     >
   >,
+
+  // Types with string index signatures should return never
+  // (string index signatures shouldn't be mistaken for the brand)
+  Expect<
+    Equal<ExtractSerializedRelationProperties<Record<string, string>>, never>
+  >,
+  Expect<
+    Equal<
+      ExtractSerializedRelationProperties<
+        Record<string, { type: string; description?: string }>
+      >,
+      never
+    >
+  >,
 ];
+
+

packages/twenty-shared/src/types/index.ts

@@ -107,6 +107,7 @@ export type { FromTo } from './FromToType';
 export { HTTPMethod } from './HttpMethod';
 export type { IsEmptyRecord } from './IsEmptyRecord.type';
 export type { IsExactly } from './IsExactly';
+export type { IsSerializedRelation } from './IsSerializedRelation.type';
 export type { LogicFunctionEvent } from './LogicFunctionEvent';
 export { MessageParticipantRole } from './MessageParticipantRole';
 export type { ModifiedProperties } from './ModifiedProperties';