Improve apps (#19256)

- simplify the base application template
- remove --exhaustive option and replace by a --example option like in
next.js https://nextjs.org/docs/app/api-reference/cli
- Fix some bugs and logs
- add a post-card app in twenty-apps/examples/

packages/twenty-apps/examples/hello-world/src/objects/example-object.ts

@@ -0,0 +1,29 @@
+import { defineObject, FieldType } from 'twenty-sdk';
+
+export const EXAMPLE_OBJECT_UNIVERSAL_IDENTIFIER =
+  '47fd9bd9-392b-4d9f-9091-9a91b1edf519';
+
+export const NAME_FIELD_UNIVERSAL_IDENTIFIER =
+  '2d9ff841-cf8e-44ec-ad8e-468455f7eebd';
+
+export default defineObject({
+  universalIdentifier: EXAMPLE_OBJECT_UNIVERSAL_IDENTIFIER,
+  nameSingular: 'exampleItem',
+  namePlural: 'exampleItems',
+  labelSingular: 'Example item',
+  labelPlural: 'Example items',
+  description: 'A sample custom object',
+  icon: 'IconBox',
+  labelIdentifierFieldMetadataUniversalIdentifier:
+    NAME_FIELD_UNIVERSAL_IDENTIFIER,
+  fields: [
+    {
+      universalIdentifier: NAME_FIELD_UNIVERSAL_IDENTIFIER,
+      type: FieldType.TEXT,
+      name: 'name',
+      label: 'Name',
+      description: 'Name of the example item',
+      icon: 'IconAbc',
+    },
+  ],
+});