The #164 reorder-accounts feature switched addImapAccount/addOutlookAccount from accountDao.upsert(...) to accountDao.insertAtEnd(...) (a @Transaction default method that stamps sortOrder before delegating to upsert), but the test's mocks/verifies still targeted upsert directly. Since MockK doesn't invoke a mocked interface's default method body, the unstubbed insertAtEnd call threw MockKException. Updated the stub/verify pairs in both add-account happy-path tests and the exactly-0 verifies in both failure-path tests to reference insertAtEnd.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>