init: add source code from src.zip

src/utils/authPortable.ts

@@ -0,0 +1,19 @@
+import { execa } from 'execa'
+import { getMacOsKeychainStorageServiceName } from 'src/utils/secureStorage/macOsKeychainHelpers.js'
+
+export async function maybeRemoveApiKeyFromMacOSKeychainThrows(): Promise<void> {
+  if (process.platform === 'darwin') {
+    const storageServiceName = getMacOsKeychainStorageServiceName()
+    const result = await execa(
+      `security delete-generic-password -a $USER -s "${storageServiceName}"`,
+      { shell: true, reject: false },
+    )
+    if (result.exitCode !== 0) {
+      throw new Error('Failed to delete keychain entry')
+    }
+  }
+}
+
+export function normalizeApiKeyForConfig(apiKey: string): string {
+  return apiKey.slice(-20)
+}