Identify agent (#17221)

# Introduction
Related to https://github.com/twentyhq/core-team-issues/issues/1989

1/ Migration, applicationId and universalIdentifier are required on
entity ( save point migration + upgrade command fallback pattern )
2/ Backfill using previous standard ids

## Test
tested prod extract

packages/twenty-server/src/engine/metadata-modules/ai/ai-agent/entities/agent.entity.ts

@@ -14,7 +14,7 @@ import {
   DEFAULT_SMART_MODEL,
   ModelId,
 } from 'src/engine/metadata-modules/ai/ai-models/constants/ai-models.const';
-import { SyncableEntity } from 'src/engine/workspace-manager/types/syncable-entity.interface';
+import { SyncableEntityRequired } from 'src/engine/workspace-manager/types/syncable-entity-required.interface';
 
 @Entity('agent')
 @Index('IDX_AGENT_ID_DELETED_AT', ['id', 'deletedAt'])
@@ -23,7 +23,7 @@ import { SyncableEntity } from 'src/engine/workspace-manager/types/syncable-enti
   where: '"deletedAt" IS NULL',
 })
 export class AgentEntity
-  extends SyncableEntity
+  extends SyncableEntityRequired
   implements Required<AgentEntity>
 {
   @PrimaryGeneratedColumn('uuid')

packages/twenty-server/src/engine/metadata-modules/flat-agent/utils/transform-agent-entity-to-flat-agent.util.ts

@@ -19,7 +19,8 @@ export const transformAgentEntityToFlatAgent = (
     responseFormat: agentEntity.responseFormat,
     workspaceId: agentEntity.workspaceId,
     isCustom: agentEntity.isCustom,
-    universalIdentifier: agentEntity.standardId || agentEntity.id,
+    // TODO remove once MakeAgentUniversalIdentifierAndApplicationIdNotNullableMigrationCommand has been run once
+    universalIdentifier: agentEntity.universalIdentifier ?? agentEntity.id,
     applicationId: agentEntity.applicationId,
     modelConfiguration: agentEntity.modelConfiguration,
     evaluationInputs: agentEntity.evaluationInputs,