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-shared/src/application/applicationType.ts

@@ -1,5 +1,6 @@
 import { type PostInstallLogicFunctionApplicationManifest } from '@/application/postInstallLogicFunctionApplicationType';
 import { type PreInstallLogicFunctionApplicationManifest } from '@/application/preInstallLogicFunctionApplicationType';
+import { type SettingsFrontComponentApplicationManifest } from '@/application/settingsFrontComponentApplicationType';
 import { type UninstallLogicFunctionApplicationManifest } from '@/application/uninstallLogicFunctionApplicationType';
 import { type ApplicationCategory } from './applicationCategoryType';
 import { type ApplicationVariables } from './applicationVariablesType';
@@ -32,10 +33,10 @@ export type ApplicationManifest = SyncableEntityOptions & {
   postInstallLogicFunction?: PostInstallLogicFunctionApplicationManifest;
   preInstallLogicFunction?: PreInstallLogicFunctionApplicationManifest;
   uninstallLogicFunction?: UninstallLogicFunctionApplicationManifest;
+  settingsFrontComponent?: SettingsFrontComponentApplicationManifest;
   /**
-   * @deprecated Custom settings tabs are no longer supported. This property is
-   * kept for backward compatibility with older manifests but is now ignored.
-   * Use typed `applicationVariables` / `serverVariables` instead.
+   * @deprecated Use `defineSettingsFrontComponent()` (exposed on the manifest
+   * as `settingsFrontComponent`) instead. This property is ignored.
    */
   settingsCustomTabFrontComponentUniversalIdentifier?: string;
   packageJsonChecksum: string | null;

packages/twenty-shared/src/application/index.ts

@@ -135,6 +135,7 @@ export type { RunAgentInput, RunAgentResult } from './runAgentType';
 export type { ServerVariables } from './server-variables.type';
 export type { ServerRouteDispatchResult } from './serverRouteDispatchResultType';
 export type { ServerRouteTriggerSettings } from './serverRouteTriggerSettingsType';
+export type { SettingsFrontComponentApplicationManifest } from './settingsFrontComponentApplicationType';
 export type { SkillManifest } from './skillManifestType';
 export type { StoredOAuthConnectionProviderConfig } from './storedOAuthConnectionProviderConfigType';
 export type { SyncableEntityOptions } from './syncableEntityOptionsType';

packages/twenty-shared/src/application/settingsFrontComponentApplicationType.ts

@@ -0,0 +1,3 @@
+export type SettingsFrontComponentApplicationManifest = {
+  universalIdentifier: string;
+};