Create the Dashboard record show page (#14423)

Closes https://github.com/twentyhq/core-team-issues/issues/1438

- Reorganized PageLayout module
- Created `DashboardRenderer` and `PageLayoutRenderer`
- Created stories for the `PageLayoutRenderer`
- Refactored the Widget components


https://github.com/user-attachments/assets/27e9ac8f-b237-4c21-8494-3fab6d65af3a

packages/twenty-front/src/modules/page-layout/constants/EmptyLayout.ts

@@ -0,0 +1,6 @@
+import { type Layouts } from 'react-grid-layout';
+
+export const EMPTY_LAYOUT: Layouts = {
+  desktop: [{ i: 'empty-placeholder', x: 0, y: 0, w: 4, h: 4, static: true }],
+  mobile: [{ i: 'empty-placeholder', x: 0, y: 0, w: 1, h: 4, static: true }],
+};