fix: restore isCustom gate in metadata label resolvers (#21432)

## Context

#21228 removed the stored `isCustom` column and, with it, the `isCustom`
early-return in `resolveObjectMetadataStandardOverride` /
`resolveFieldMetadataStandardOverride`, on the assumption that falling
through the `standardOverrides` checks was equivalent.

It isn't: custom object/field labels now reach the Lingui lookup. A
custom label that collides with a standard catalog string (e.g. a custom
field labeled "Status") gets translated for non-English locales against
the user's intent, and every other custom label pays a hash + catalog
miss — and, in production, an "Uncompiled message detected" warning
(#21415) — on each metadata resolution.

## Fix

Restore the gate. `isCustom` is no longer stored, so call sites that
build the resolver input from flat entities (dataloader,
minimal-metadata, view controller, command-menu-item navigation context)
derive it via `belongsToTwentyStandardApp`; GraphQL resolvers keep
passing DTOs, which already carry the derived value.

## Testing

- Unit tests for both resolvers, including a new regression test: a
custom label matching a standard catalog entry is returned verbatim,
Lingui never called.

---------

Co-authored-by: Weiko <corentin@twenty.com>

packages/twenty-server/src/engine/metadata-modules/view/controllers/view.controller.ts

@@ -25,6 +25,7 @@ import { WorkspaceAuthGuard } from 'src/engine/guards/workspace-auth.guard';
 import { WorkspaceManyOrAllFlatEntityMapsCacheService } from 'src/engine/metadata-modules/flat-entity/services/workspace-many-or-all-flat-entity-maps-cache.service';
 import { findFlatEntityByIdInFlatEntityMaps } from 'src/engine/metadata-modules/flat-entity/utils/find-flat-entity-by-id-in-flat-entity-maps.util';
 import { resolveObjectMetadataStandardOverride } from 'src/engine/metadata-modules/object-metadata/utils/resolve-object-metadata-standard-override.util';
+import { belongsToTwentyStandardApp } from 'src/engine/metadata-modules/utils/belongs-to-twenty-standard-app.util';
 import { CreateViewPermissionGuard } from 'src/engine/metadata-modules/view-permissions/guards/create-view-permission.guard';
 import { DeleteViewPermissionGuard } from 'src/engine/metadata-modules/view-permissions/guards/delete-view-permission.guard';
 import { UpdateViewPermissionGuard } from 'src/engine/metadata-modules/view-permissions/guards/update-view-permission.guard';
@@ -216,6 +217,7 @@ export class ViewController {
               labelSingular: objectMetadata.labelSingular,
               description: objectMetadata.description ?? undefined,
               icon: objectMetadata.icon ?? undefined,
+              isCustom: !belongsToTwentyStandardApp(objectMetadata),
               standardOverrides: objectMetadata.standardOverrides ?? undefined,
             },
             'labelPlural',

packages/twenty-server/src/engine/metadata-modules/view/resolvers/view.resolver.ts

@@ -74,6 +74,7 @@ export class ViewResolver {
             labelSingular: objectMetadata.labelSingular,
             description: objectMetadata.description ?? undefined,
             icon: objectMetadata.icon ?? undefined,
+            isCustom: objectMetadata.isCustom,
             standardOverrides: objectMetadata.standardOverrides ?? undefined,
           },
           'labelPlural',