[CHORE] Avoid isDefined duplicated reference, move it to twenty-shared (#9967)

# Introduction
Avoid having multiple `isDefined` definition across our pacakges
Also avoid importing `isDefined` from `twenty-ui` which exposes a huge
barrel for a such little util function

## In a nutshell
Removed own `isDefined.ts` definition from `twenty-ui` `twenty-front`
and `twenty-server` to move it to `twenty-shared`.
Updated imports for each packages, and added explicit dependencies to
`twenty-shared` if not already in place

Related PR https://github.com/twentyhq/twenty/pull/9941

packages/twenty-server/src/engine/core-modules/jwt/services/jwt-wrapper.service.ts

@@ -4,13 +4,13 @@ import { JwtService, JwtSignOptions, JwtVerifyOptions } from '@nestjs/jwt';
 import { createHash } from 'crypto';
 
 import * as jwt from 'jsonwebtoken';
+import { isDefined } from 'twenty-shared';
 
 import {
   AuthException,
   AuthExceptionCode,
 } from 'src/engine/core-modules/auth/auth.exception';
 import { EnvironmentService } from 'src/engine/core-modules/environment/environment.service';
-import { isDefined } from 'src/utils/is-defined';
 
 export type WorkspaceTokenType =
   | 'ACCESS'