Generate GQL schema based on applicationId (#17860)

## Add application-scoped GraphQL schema generation

When an application token is used to authenticate, the `/graphql` schema
is now dynamically filtered to only include entities belonging to that
application (plus the Twenty Standard Application). This enables
third-party applications and the SDK to introspect a schema that is
relevant to their scope, rather than seeing the full workspace schema
with all custom objects.

### Changes

- **New `generateApplicationToken` mutation** on the `/metadata`
endpoint, allowing callers to exchange an API key for an
application-scoped JWT token
- **Schema filtering by application** in `WorkspaceSchemaFactory` — when
`request.application` is present (from an application token), flat
entity maps are filtered by `[appId, standardAppId]` before schema
generation
- **Per-app caching** — both the Yoga in-memory cache and Redis cache
now include the `appId` in their keys to avoid serving wrong schemas
- **Consolidated `getSubFlatEntityMapsByApplicationIdsOrThrow`** —
unified the single-ID and multi-ID filtering utilities into one
- **Integration tests** covering token generation (admin + API key auth)
and schema introspection filtering (standard app token excludes custom
objects)

Schema generated on seeds with applicationToken (see that pets is
missing)
<img width="782" height="994" alt="image"
src="https://github.com/user-attachments/assets/82510031-0965-435d-bc26-77c9f5d74e1f"
/>

packages/twenty-server/src/engine/workspace-manager/twenty-standard-application/services/twenty-standard-application.service.ts

@@ -8,7 +8,7 @@ import { TwentyConfigService } from 'src/engine/core-modules/twenty-config/twent
 import { MetadataFlatEntity } from 'src/engine/metadata-modules/flat-entity/types/metadata-flat-entity.type';
 import { findFlatEntityByUniversalIdentifier } from 'src/engine/metadata-modules/flat-entity/utils/find-flat-entity-by-universal-identifier.util';
 import { getMetadataFlatEntityMapsKey } from 'src/engine/metadata-modules/flat-entity/utils/get-metadata-flat-entity-maps-key.util';
-import { getSubFlatEntityMapsByApplicationIdOrThrow } from 'src/engine/metadata-modules/flat-entity/utils/get-sub-flat-entity-maps-by-application-id-or-throw.util';
+import { getSubFlatEntityMapsByApplicationIdsOrThrow } from 'src/engine/metadata-modules/flat-entity/utils/get-sub-flat-entity-maps-by-application-ids-or-throw.util';
 import { FlatView } from 'src/engine/metadata-modules/flat-view/types/flat-view.type';
 import { GlobalWorkspaceOrmManager } from 'src/engine/twenty-orm/global-workspace-datasource/global-workspace-orm.manager';
 import { buildSystemAuthContext } from 'src/engine/twenty-orm/utils/build-system-auth-context.util';
@@ -94,10 +94,10 @@ export class TwentyStandardApplicationService {
       const fromFlatEntityMaps =
         fromTwentyStandardAllFlatEntityMaps[flatEntityMapsKey];
       const fromTo = {
-        from: getSubFlatEntityMapsByApplicationIdOrThrow<
+        from: getSubFlatEntityMapsByApplicationIdsOrThrow<
           MetadataFlatEntity<typeof metadataName>
         >({
-          applicationId: twentyStandardFlatApplication.id,
+          applicationIds: [twentyStandardFlatApplication.id],
           flatEntityMaps: fromFlatEntityMaps,
         }),
         to: toTwentyStandardAllFlatEntityMaps[flatEntityMapsKey],