[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/settings/data-model/fields/forms/components/SettingsDataModelFieldIconLabelForm.tsx

@@ -12,12 +12,12 @@ import { IconPicker } from '@/ui/input/components/IconPicker';
 import { TextInput } from '@/ui/input/components/TextInput';
 import { useTheme } from '@emotion/react';
 import { useLingui } from '@lingui/react/macro';
+import { isDefined } from 'twenty-shared';
 import {
   AppTooltip,
   Card,
   IconInfoCircle,
   IconRefresh,
-  isDefined,
   TooltipDelay,
 } from 'twenty-ui';
 import { computeMetadataNameFromLabel } from '~/pages/settings/data-model/utils/compute-metadata-name-from-label.utils';