[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-front/src/modules/auth/sign-in-up/components/SignInUpGlobalScopeForm.tsx

@@ -26,7 +26,7 @@ import { authProvidersState } from '@/client-config/states/authProvidersState';
 import { useRedirectToWorkspaceDomain } from '@/domain-manager/hooks/useRedirectToWorkspaceDomain';
 import { SnackBarVariant } from '@/ui/feedback/snack-bar-manager/components/SnackBar';
 import { useSnackBar } from '@/ui/feedback/snack-bar-manager/hooks/useSnackBar';
-import { isDefined } from '~/utils/isDefined';
+import { isDefined } from 'twenty-shared';
 
 const StyledContentContainer = styled(motion.div)`
   margin-bottom: ${({ theme }) => theme.spacing(8)};