feat: manually implement joinColumn (#6022)

This PR introduce a new decorator named `@WorkspaceJoinColumn`, the goal
of this one is to manually declare the join columns inside the workspace
entities, so we don't have to rely on `ObjectRecord` type.

This decorator can be used that way:

```typescript
  @WorkspaceRelation({
    standardId: ACTIVITY_TARGET_STANDARD_FIELD_IDS.company,
    type: RelationMetadataType.MANY_TO_ONE,
    label: 'Company',
    description: 'ActivityTarget company',
    icon: 'IconBuildingSkyscraper',
    inverseSideTarget: () => CompanyWorkspaceEntity,
    inverseSideFieldKey: 'activityTargets',
  })
  @WorkspaceIsNullable()
  company: Relation<CompanyWorkspaceEntity> | null;

  // The argument is the name of the relation above
  @WorkspaceJoinColumn('company')
  companyId: string | null;
```

packages/twenty-server/src/engine/twenty-orm/storage/metadata-args.storage.ts

@@ -6,6 +6,7 @@ import { WorkspaceEntityMetadataArgs } from 'src/engine/twenty-orm/interfaces/wo
 import { WorkspaceRelationMetadataArgs } from 'src/engine/twenty-orm/interfaces/workspace-relation-metadata-args.interface';
 import { WorkspaceExtendedEntityMetadataArgs } from 'src/engine/twenty-orm/interfaces/workspace-extended-entity-metadata-args.interface';
 import { WorkspaceIndexMetadataArgs } from 'src/engine/twenty-orm/interfaces/workspace-index-metadata-args.interface';
+import { WorkspaceJoinColumnsMetadataArgs } from 'src/engine/twenty-orm/interfaces/workspace-join-columns-metadata-args.interface';
 
 export class MetadataArgsStorage {
   private readonly entities: WorkspaceEntityMetadataArgs[] = [];
@@ -15,6 +16,7 @@ export class MetadataArgsStorage {
   private readonly dynamicRelations: WorkspaceDynamicRelationMetadataArgs[] =
     [];
   private readonly indexes: WorkspaceIndexMetadataArgs[] = [];
+  private readonly joinColumns: WorkspaceJoinColumnsMetadataArgs[] = [];
 
   addEntities(...entities: WorkspaceEntityMetadataArgs[]): void {
     this.entities.push(...entities);
@@ -44,6 +46,10 @@ export class MetadataArgsStorage {
     this.dynamicRelations.push(...dynamicRelations);
   }
 
+  addJoinColumns(...joinColumns: WorkspaceJoinColumnsMetadataArgs[]): void {
+    this.joinColumns.push(...joinColumns);
+  }
+
   filterEntities(
     target: Function | string,
   ): WorkspaceEntityMetadataArgs | undefined;
@@ -123,6 +129,20 @@ export class MetadataArgsStorage {
     return this.filterByTarget(this.dynamicRelations, target);
   }
 
+  filterJoinColumns(
+    target: Function | string,
+  ): WorkspaceJoinColumnsMetadataArgs[];
+
+  filterJoinColumns(
+    target: (Function | string)[],
+  ): WorkspaceJoinColumnsMetadataArgs[];
+
+  filterJoinColumns(
+    target: (Function | string) | (Function | string)[],
+  ): WorkspaceJoinColumnsMetadataArgs[] {
+    return this.filterByTarget(this.joinColumns, target);
+  }
+
   protected filterByTarget<T extends { target: Function | string }>(
     array: T[],
     target: (Function | string) | (Function | string)[],