Compute output schema on frontend (#16530)

Fixes https://github.com/twentyhq/core-team-issues/issues/1382

Current issue : all step output schemas are computed and stored on
backend side. Which means that, when the database schema is updated -
like a field creation - steps needs to be deleted an recreated. Which is
invisible to users.

Solution : schema generation is moved on frontend side

1. Coming on the page the first time, the schema is populated for all
steps except a few ones that are handled differently (Code, Webhook,
http node, Agent)

2. A separated state allow to determine if a step needs a recomputation.

3. The user only needs a refresh to see the whole schema re-computed

Follow-up:
- check if remaining backend steps could be moved to runtime
computation. But Code will still require storage.
- Clean backend service that is not used anymore

packages/twenty-server/src/modules/workflow/workflow-builder/workflow-schema/workflow-schema.workspace-service.ts

@@ -175,15 +175,12 @@ export class WorkflowSchemaWorkspaceService {
     workspaceId: string;
     workflowVersionId: string;
   }): Promise<WorkflowAction> {
-    // We don't enrich on the fly for code and HTTP request workflow actions.
-    // For code actions, OutputSchema is computed and updated when testing the serverless function.
-    // For HTTP requests, OutputSchema is determined by the example response input
-    // AI agent OutputSchema is enriched from agent's responseFormat
-    if (
-      [WorkflowActionType.CODE, WorkflowActionType.HTTP_REQUEST].includes(
-        step.type,
-      )
-    ) {
+    const BACKEND_ENRICHED_TYPES = [
+      WorkflowActionType.AI_AGENT,
+      WorkflowActionType.ITERATOR,
+    ];
+
+    if (!BACKEND_ENRICHED_TYPES.includes(step.type)) {
       return step;
     }