feat(twenty-front): relation traversal in filter dropdown (stacked) (#20533)

**Stacked on #20527** 




https://github.com/user-attachments/assets/48995655-401a-4c35-8094-e88da8408bdd





## Summary

Surfaces the one-hop relation traversal added in #20527 through the
existing **composite sub-field dropdown pattern**. Clicking a
MANY_TO_ONE relation field in the "+ Filter" picker now opens the same
second-level dropdown that composite fields (FULL_NAME, ADDRESS,
CURRENCY, etc.) already use — populated with the target object's
filterable fields. Picking one (e.g. `Company → Name`) builds a filter
that serializes to the nested GraphQL filter the backend now accepts: `{
company: { name: { ilike: "%X%" } } }`.

No new components. The whole feature reuses
`AdvancedFilterSubFieldSelectMenu` + the existing
`subFieldNameUsedInDropdownComponentState` + the existing `MenuItem
hasSubMenu` indicator. Only the conditions that gate the sub-menu (and
the sub-menu's content for relations) were broadened.

## What landed

| File | Change |
|---|---|
| `ObjectFilterDropdownFilterSelectMenuItem` | Sub-menu chevron now
shows on MANY_TO_ONE relations (`isManyToOneRelationField` util). |
| `AdvancedFilterFieldSelectMenu` | Relation clicks open the sub-menu
alongside composite clicks. |
| `AdvancedFilterSubFieldSelectMenu` | New branch: when the sub-menu
type is `'RELATION'`, render the target object's filterable fields via
`useFilterableFieldMetadataItems(targetObjectMetadataId)`. Composite
logic untouched. |
| `objectFilterDropdownSubMenuFieldType` state | Widened to accept a
`'RELATION'` sentinel. Role-permissions sub-field menu narrows it back
out (it doesn't traverse relations). |
| `useSelectFieldUsedInAdvancedFilterDropdown` | New optional
`targetFieldMetadataItem` arg. When present, the stored RecordFilter's
`type` is the target field's type so the operand picker and value input
render the target's operands (`'TEXT'` operators when filtering
`company.name`, etc.). |
| `turnRecordFilterIntoGqlOperationFilter` (shared) | When the filter
targets a `RELATION` field with a `subFieldName`, synthesize a
field-metadata for the target, recurse to build the inner filter, then
wrap it under the relation field's name → `{ relationName: {
targetFieldName: { ...operator } } }`. |

`RecordFilter.subFieldName` stays narrowly typed as
`CompositeFieldSubFieldName` so the wide downstream consumers
(`shouldShowFilterTextInput`, composite handlers in the serializer,
etc.) don't change. The relation target field's name is stored through a
narrowly-scoped cast at the dropdown's storage point — the serializer
checks `filter.type === 'RELATION'` before interpreting it as a target
field name, so the cast can't be mis-read by composite-only code paths.

## Test plan

- [ ] Open a table view on People, click "+ Filter", click "Company" →
sub-menu opens with Company's filterable fields
- [ ] Pick "Name" → operand picker shows TEXT operators (Contains,
Equals, …)
- [ ] Type "Airbnb" → filter applies, table shows people whose company
name contains "Airbnb"
- [ ] Verify network tab: the GraphQL filter variable is `{ company: {
name: { ilike: "%Airbnb%" } } }`
- [ ] Same flow with a composite target field (e.g. `Company →
annualRecurringRevenue → amountMicros`) — should work end-to-end
(backend supports composite-within-relation; #20527 has an integration
test covering this)
- [ ] Composite fields (FULL_NAME, ADDRESS) still open their normal
sub-menu and filter correctly — no regression
- [ ] Role-permissions field-select sub-field menu is unaffected (it
bails out early on the RELATION sentinel)

## Out of scope

- ONE_TO_MANY traversal (no backend support yet)
- Aggregates (`people.count > 5`)
- Persisting relation-traversal filters into a saved view (ViewFilter
has no `relationPath` column yet; that's a separate slice)
- REST API DSL changes
- AI Tools

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

packages/twenty-server/src/engine/workspace-manager/twenty-standard-application/utils/view-filter/create-standard-view-filter-flat-metadata.util.ts

@@ -96,6 +96,8 @@ export const createStandardViewFilterFlatMetadata = <
     operand,
     value,
     subFieldName,
+    relationTargetFieldMetadataId: null,
+    relationTargetFieldMetadataUniversalIdentifier: null,
     positionInViewFilterGroup,
     createdAt: now,
     updatedAt: now,

packages/twenty-server/src/engine/workspace-manager/workspace-migration/workspace-migration-runner/action-handlers/view-filter/services/create-view-filter-action-handler.service.ts

@@ -26,12 +26,16 @@ export class CreateViewFilterActionHandlerService extends WorkspaceMigrationRunn
     flatApplication,
     workspaceId,
   }: WorkspaceMigrationActionRunnerArgs<UniversalCreateViewFilterAction>): Promise<FlatCreateViewFilterAction> {
-    const { fieldMetadataId, viewId, viewFilterGroupId } =
-      resolveUniversalRelationIdentifiersToIds({
-        flatEntityMaps: allFlatEntityMaps,
-        metadataName: action.metadataName,
-        universalForeignKeyValues: action.flatEntity,
-      });
+    const {
+      fieldMetadataId,
+      viewId,
+      viewFilterGroupId,
+      relationTargetFieldMetadataId,
+    } = resolveUniversalRelationIdentifiersToIds({
+      flatEntityMaps: allFlatEntityMaps,
+      metadataName: action.metadataName,
+      universalForeignKeyValues: action.flatEntity,
+    });
 
     const emptyUniversalForeignKeyAggregators =
       getUniversalFlatEntityEmptyForeignKeyAggregators({
@@ -45,6 +49,7 @@ export class CreateViewFilterActionHandlerService extends WorkspaceMigrationRunn
         fieldMetadataId,
         viewId,
         viewFilterGroupId,
+        relationTargetFieldMetadataId,
         id: action.id ?? v4(),
         applicationId: flatApplication.id,
         workspaceId,