Fix env not optional + serverless logging (#15186)

Several fixes after discussing with @BOHEUS 
- set applicationManifest env key optional
- fix server local serverless function logging (introduces a new env
variable `SERVERLESS_LOGS_ENABLED` defaulting to false)

packages/twenty-server/src/engine/core-modules/applicationVariable/application-variable.service.ts

@@ -4,6 +4,7 @@ import { isDefined } from 'twenty-shared/utils';
 import { In, Not, Repository } from 'typeorm';
 
 import { ApplicationVariable } from 'src/engine/core-modules/applicationVariable/application-variable.entity';
+import { EnvManifest } from 'src/engine/core-modules/application/types/application.types';
 
 export class ApplicationVariableService {
   constructor(
@@ -28,14 +29,7 @@ export class ApplicationVariableService {
     env,
     applicationId,
   }: {
-    env: Record<
-      string,
-      {
-        value?: string;
-        description?: string;
-        isSecret: boolean;
-      }
-    >;
+    env?: EnvManifest;
     applicationId: string;
   }) {
     if (!isDefined(env)) {