Update twenty-front commands (#4667)

# This PR

- Moves dev and ci scripts to the `project.json` file in the
twenty-front package
- Adds a project.json file in the root of the project with the main
start command that start both twenty-server and twenty-front
applications concurrently
- Updates the script command of the root project with the start:prod
command (replacing the start command which will be used in dev with the
help of nx)
- Add a start:prod command in the twenty-front app, replacing the start
command (now used for dev purpose)

Issue ref #4645 

@charlesBochet @FelixMalfait please let me know how can I improve it

---------

Co-authored-by: Thaïs Guigon <guigon.thais@gmail.com>

packages/twenty-front/src/modules/activities/hooks/__tests__/useCreateActivityInCache.test.tsx

@@ -83,12 +83,10 @@ describe('useCreateActivityInCache', () => {
     act(() => {
       const res = result.current.createActivityInCache({
         type: 'Note',
-        targetableObjects: [
-          {
-            targetObjectNameSingular: 'person',
-            id: '1234',
-          },
-        ],
+        targetObject: {
+          targetObjectNameSingular: 'person',
+          id: '1234',
+        },
       });
 
       expect(res.createdActivityInCache).toHaveProperty('id');