feat(applications): restore the application custom settings tab (#23256)

## Summary

Restores the application **custom settings tab** feature that was
removed in #22156. This reverts that removal so applications can again
expose a custom settings tab via a front component.

## Changes

- Restore the `SettingsApplicationCustomTab` component and its tab
entry/rendering in `SettingsApplicationDetails`.
- `ApplicationManifestMigrationService` syncs
`settingsCustomTabFrontComponent` from application manifests again
(`syncDefaultRoleAndSettingsCustomTab`), resolving the front component
from `settingsCustomTabFrontComponentUniversalIdentifier`.
- Remove the deprecation annotations added by #22156:
- `ApplicationDTO.settingsCustomTabFrontComponentId` (drop GraphQL
`@deprecated`)
-
`ApplicationManifest.settingsCustomTabFrontComponentUniversalIdentifier`
- the `settingsCustomTabFrontComponentId` column comment on
`ApplicationEntity`
- Regenerate the corresponding GraphQL schema/types to drop the
`@deprecated` reason.

The DB column was never dropped, so no schema migration is required.


---
_Generated by [Claude
Code](https://claude.ai/code/session_01A6aoLa5kZjba9C3uwo6nay)_

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---------

Co-authored-by: Félix Malfait <felix.malfait@gmail.com>

packages/twenty-server/src/engine/core-modules/application/application-manifest/application-manifest-migration.service.ts

@@ -249,7 +249,7 @@ export class ApplicationManifestMigrationService {
     );
 
     if (!dryRun) {
-      await this.syncDefaultRole({
+      await this.syncDefaultRoleAndSettingsFrontComponent({
         manifest,
         workspaceId,
         ownerFlatApplication,
@@ -262,7 +262,7 @@ export class ApplicationManifestMigrationService {
     };
   }
 
-  private async syncDefaultRole({
+  private async syncDefaultRoleAndSettingsFrontComponent({
     manifest,
     workspaceId,
     ownerFlatApplication,
@@ -271,10 +271,13 @@ export class ApplicationManifestMigrationService {
     workspaceId: string;
     ownerFlatApplication: FlatApplication;
   }) {
-    const { flatRoleMaps: refreshedFlatRoleMaps } =
-      await this.workspaceCacheService.getOrRecompute(workspaceId, [
-        'flatRoleMaps',
-      ]);
+    const {
+      flatRoleMaps: refreshedFlatRoleMaps,
+      flatFrontComponentMaps: refreshedFlatFrontComponentMaps,
+    } = await this.workspaceCacheService.getOrRecompute(workspaceId, [
+      'flatRoleMaps',
+      'flatFrontComponentMaps',
+    ]);
 
     let defaultRoleId: string | null = null;
 
@@ -299,11 +302,31 @@ export class ApplicationManifestMigrationService {
       }
     }
 
-    if (isDefined(defaultRoleId)) {
-      await this.applicationService.update(ownerFlatApplication.id, {
-        workspaceId,
-        defaultRoleId,
+    let settingsCustomTabFrontComponentId: string | null = null;
+
+    const settingsFrontComponentUniversalIdentifier =
+      manifest.application.settingsFrontComponent?.universalIdentifier;
+
+    if (isDefined(settingsFrontComponentUniversalIdentifier)) {
+      const flatFrontComponent = findFlatEntityByUniversalIdentifier({
+        flatEntityMaps: refreshedFlatFrontComponentMaps,
+        universalIdentifier: settingsFrontComponentUniversalIdentifier,
       });
+
+      if (!isDefined(flatFrontComponent)) {
+        throw new ApplicationException(
+          `Failed to resolve front component for settings front component universalIdentifier ${settingsFrontComponentUniversalIdentifier}`,
+          ApplicationExceptionCode.ENTITY_NOT_FOUND,
+        );
+      }
+
+      settingsCustomTabFrontComponentId = flatFrontComponent.id;
     }
+
+    await this.applicationService.update(ownerFlatApplication.id, {
+      workspaceId,
+      settingsCustomTabFrontComponentId,
+      ...(isDefined(defaultRoleId) ? { defaultRoleId } : {}),
+    });
   }
 }

packages/twenty-server/src/engine/core-modules/application/application-manifest/converters/from-front-component-manifest-to-universal-flat-front-component.util.ts

@@ -5,10 +5,12 @@ import { type UniversalFlatFrontComponent } from 'src/engine/workspace-manager/w
 export const fromFrontComponentManifestToUniversalFlatFrontComponent = ({
   frontComponentManifest,
   applicationUniversalIdentifier,
+  isSettingsFrontComponent,
   now,
 }: {
   frontComponentManifest: FrontComponentManifest;
   applicationUniversalIdentifier: string;
+  isSettingsFrontComponent: boolean;
   now: string;
 }): UniversalFlatFrontComponent => {
   return {
@@ -20,7 +22,10 @@ export const fromFrontComponentManifestToUniversalFlatFrontComponent = ({
     builtComponentPath: frontComponentManifest.builtComponentPath,
     componentName: frontComponentManifest.componentName,
     builtComponentChecksum: frontComponentManifest.builtComponentChecksum,
-    isHeadless: frontComponentManifest.isHeadless ?? false,
+    // A settings front component always renders visible UI.
+    isHeadless: isSettingsFrontComponent
+      ? false
+      : (frontComponentManifest.isHeadless ?? false),
     usesSdkClient: frontComponentManifest.usesSdkClient ?? false,
     createdAt: now,
     updatedAt: now,

packages/twenty-server/src/engine/core-modules/application/application-manifest/services/compute-application-manifest-all-universal-flat-entity-maps.service.ts

@@ -215,12 +215,18 @@ export class ComputeApplicationManifestAllUniversalFlatEntityMapsService {
       });
     }
 
+    const settingsFrontComponentUniversalIdentifier =
+      manifest.application.settingsFrontComponent?.universalIdentifier;
+
     for (const frontComponentManifest of manifest.frontComponents) {
       addUniversalFlatEntityToUniversalFlatEntityMapsThroughMutationOrThrow({
         universalFlatEntity:
           fromFrontComponentManifestToUniversalFlatFrontComponent({
             frontComponentManifest,
             applicationUniversalIdentifier,
+            isSettingsFrontComponent:
+              frontComponentManifest.universalIdentifier ===
+              settingsFrontComponentUniversalIdentifier,
             now,
           }),
         universalFlatEntityMapsToMutate:

packages/twenty-server/src/engine/core-modules/application/application.entity.ts

@@ -113,11 +113,6 @@ export class ApplicationEntity extends WorkspaceRelatedEntity {
   @Field(() => RoleDTO, { nullable: true })
   defaultRole: RoleDTO | null;
 
-  /**
-   * @deprecated Custom settings tabs are no longer supported. The column is
-   * kept (not dropped) so existing installations upgrade cleanly, but the
-   * value is no longer read or synced from manifests.
-   */
   @Column({ nullable: true, type: 'uuid' })
   settingsCustomTabFrontComponentId: string | null;
 

packages/twenty-server/src/engine/core-modules/application/dtos/application.dto.ts

@@ -95,17 +95,9 @@ export class ApplicationDTO {
   @Field({ nullable: true })
   defaultRoleId?: string;
 
-  /**
-   * @deprecated Custom settings tabs are no longer supported. Kept for
-   * backward compatibility with existing installations; the value is ignored.
-   */
   @IsOptional()
   @IsUUID()
-  @Field(() => UUIDScalarType, {
-    nullable: true,
-    deprecationReason:
-      'Custom settings tabs are no longer supported. This field is ignored.',
-  })
+  @Field(() => UUIDScalarType, { nullable: true })
   settingsCustomTabFrontComponentId?: string;
 
   @IsOptional()