Support Skill in manifest (#18092)

# Introduction
Support skill in manifest, pre-requisite for the twenty standard app
migration

packages/create-twenty-app/src/utils/__tests__/app-template.spec.ts

@@ -1,8 +1,8 @@
-import * as fs from 'fs-extra';
-import { join } from 'path';
-import { tmpdir } from 'os';
-import { copyBaseApplicationProject } from '@/utils/app-template';
 import { type ExampleOptions } from '@/types/scaffolding-options';
+import { copyBaseApplicationProject } from '@/utils/app-template';
+import * as fs from 'fs-extra';
+import { tmpdir } from 'os';
+import { join } from 'path';
 
 // Mock fs-extra's copy function to skip copying base template (not available during tests)
 jest.mock('fs-extra', () => {
@@ -23,11 +23,13 @@ const ALL_EXAMPLES: ExampleOptions = {
   includeExampleFrontComponent: true,
   includeExampleView: true,
   includeExampleNavigationMenuItem: true,
+  includeExampleSkill: true,
 };
 
 const NO_EXAMPLES: ExampleOptions = {
   includeExampleObject: false,
   includeExampleField: false,
+  includeExampleSkill: false,
   includeExampleLogicFunction: false,
   includeExampleFrontComponent: false,
   includeExampleView: false,
@@ -437,6 +439,7 @@ describe('copyBaseApplicationProject', () => {
           exampleOptions: {
             includeExampleObject: false,
             includeExampleField: false,
+            includeExampleSkill: false,
             includeExampleLogicFunction: false,
             includeExampleFrontComponent: true,
             includeExampleView: false,
@@ -472,6 +475,7 @@ describe('copyBaseApplicationProject', () => {
           appDirectory: testAppDirectory,
           exampleOptions: {
             includeExampleObject: false,
+            includeExampleSkill: false,
             includeExampleField: false,
             includeExampleLogicFunction: true,
             includeExampleFrontComponent: false,

packages/create-twenty-app/src/utils/app-template.ts

@@ -89,6 +89,14 @@ export const copyBaseApplicationProject = async ({
     });
   }
 
+  if (exampleOptions.includeExampleSkill) {
+    await createExampleSkill({
+      appDirectory: sourceFolderPath,
+      fileFolder: 'skills',
+      fileName: 'example-skill.ts',
+    });
+  }
+
   await createDefaultPostInstallFunction({
     appDirectory: sourceFolderPath,
     fileFolder: 'logic-functions',
@@ -424,6 +432,36 @@ export default defineNavigationMenuItem({
   await fs.writeFile(join(appDirectory, fileFolder ?? '', fileName), content);
 };
 
+const createExampleSkill = async ({
+  appDirectory,
+  fileFolder,
+  fileName,
+}: {
+  appDirectory: string;
+  fileFolder?: string;
+  fileName: string;
+}) => {
+  const universalIdentifier = v4();
+
+  const content = `import { defineSkill } from 'twenty-sdk';
+
+export const EXAMPLE_SKILL_UNIVERSAL_IDENTIFIER =
+  '${universalIdentifier}';
+
+export default defineSkill({
+  universalIdentifier: EXAMPLE_SKILL_UNIVERSAL_IDENTIFIER,
+  name: 'example-skill',
+  label: 'Example Skill',
+  description: 'A sample skill for your application',
+  icon: 'IconBrain',
+  content: 'Add your skill instructions here. Skills provide context and capabilities to AI agents.',
+});
+`;
+
+  await fs.ensureDir(join(appDirectory, fileFolder ?? ''));
+  await fs.writeFile(join(appDirectory, fileFolder ?? '', fileName), content);
+};
+
 const createApplicationConfig = async ({
   displayName,
   description,