[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/ui/layout/hooks/useShowAuthModal.ts

@@ -6,9 +6,9 @@ import { useOnboardingStatus } from '@/onboarding/hooks/useOnboardingStatus';
 import { AppPath } from '@/types/AppPath';
 import { isDefaultLayoutAuthModalVisibleState } from '@/ui/layout/states/isDefaultLayoutAuthModalVisibleState';
 import { useSubscriptionStatus } from '@/workspace/hooks/useSubscriptionStatus';
+import { isDefined } from 'twenty-shared';
 import { OnboardingStatus, SubscriptionStatus } from '~/generated/graphql';
 import { useIsMatchingLocation } from '~/hooks/useIsMatchingLocation';
-import { isDefined } from '~/utils/isDefined';
 
 export const useShowAuthModal = () => {
   const isMatchingLocation = useIsMatchingLocation();