test: add getOctokit integration tests for multi-token usage

Verifies the real getOctokit from @actions/github creates functional
Octokit clients when invoked through callAsyncFunction, ensuring:
- Secondary clients have full REST/GraphQL API surface
- Secondary clients are independent from primary github client
- GHES base URL option is accepted
- Multiple tokens produce distinct client instances

__test__/getoctokit-integration.test.ts

@@ -0,0 +1,85 @@
+/* eslint-disable @typescript-eslint/no-explicit-any */
+
+import {getOctokit} from '@actions/github'
+import {callAsyncFunction} from '../src/async-function'
+
+describe('getOctokit integration via callAsyncFunction', () => {
+  test('real getOctokit creates a functional Octokit client in script scope', async () => {
+    const result = await callAsyncFunction(
+      {getOctokit} as any,
+      `
+        const client = getOctokit('fake-token-for-test')
+        return {
+          hasRest: typeof client.rest === 'object',
+          hasGraphql: typeof client.graphql === 'function',
+          hasRequest: typeof client.request === 'function',
+          hasIssues: typeof client.rest.issues === 'object',
+          hasPulls: typeof client.rest.pulls === 'object'
+        }
+      `
+    )
+
+    expect(result).toEqual({
+      hasRest: true,
+      hasGraphql: true,
+      hasRequest: true,
+      hasIssues: true,
+      hasPulls: true
+    })
+  })
+
+  test('secondary client is independent from primary github client', async () => {
+    const primary = getOctokit('primary-token')
+
+    const result = await callAsyncFunction(
+      {github: primary, getOctokit} as any,
+      `
+        const secondary = getOctokit('secondary-token')
+        return {
+          bothHaveRest: typeof github.rest === 'object' && typeof secondary.rest === 'object',
+          areDistinct: github !== secondary
+        }
+      `
+    )
+
+    expect(result).toEqual({
+      bothHaveRest: true,
+      areDistinct: true
+    })
+  })
+
+  test('getOctokit accepts options for GHES base URL', async () => {
+    const result = await callAsyncFunction(
+      {getOctokit} as any,
+      `
+        const client = getOctokit('fake-token', {
+          baseUrl: 'https://ghes.example.com/api/v3'
+        })
+        return typeof client.rest === 'object'
+      `
+    )
+
+    expect(result).toBe(true)
+  })
+
+  test('multiple getOctokit calls produce independent clients with different tokens', async () => {
+    const result = await callAsyncFunction(
+      {getOctokit} as any,
+      `
+        const clientA = getOctokit('token-a')
+        const clientB = getOctokit('token-b')
+        return {
+          aHasRest: typeof clientA.rest === 'object',
+          bHasRest: typeof clientB.rest === 'object',
+          areDistinct: clientA !== clientB
+        }
+      `
+    )
+
+    expect(result).toEqual({
+      aHasRest: true,
+      bHasRest: true,
+      areDistinct: true
+    })
+  })
+})