1774 extensibility v1 create an exhaustive documentation readme or dedicated section in twenty contributing doc (#16751)

As title

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src="https://github.com/user-attachments/assets/e2dc7e12-72e3-4ca3-ac7b-a94de547f82a"
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packages/twenty-shared/src/application/roleManifestType.ts

@@ -56,7 +56,6 @@ export type RoleManifest = SyncableEntityOptions & {
   canBeAssignedToUsers?: boolean;
   canBeAssignedToAgents?: boolean;
   canBeAssignedToApiKeys?: boolean;
-  canBeAssignedToApplications?: boolean;
   objectPermissions?: ObjectPermission[];
   fieldPermissions?: FieldPermission[];
   permissionFlags?: PermissionFlagType[];