[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/command-menu/components/CommandMenuRouter.tsx

@@ -4,7 +4,7 @@ import { COMMAND_MENU_PAGES_CONFIG } from '@/command-menu/constants/CommandMenuP
 import { commandMenuPageState } from '@/command-menu/states/commandMenuPageState';
 import styled from '@emotion/styled';
 import { useRecoilValue } from 'recoil';
-import { isDefined } from 'twenty-ui';
+import { isDefined } from 'twenty-shared';
 
 const StyledCommandMenuContent = styled.div`
   flex: 1;