Adds an on-device test proving PruneWorker/BackfillWorker defer (Result.retry())
while the encrypted cache is locked, using the REAL EncryptedCacheGuard instead of
the mocked guard the JVM PruneWorkerTest/BackfillWorkerTest use (issue #225). The
locked state is reproduced with no device auth by mocking SettingsRepository (the
same pattern DatabaseProvisionerInstrumentedTest already uses) and leaving a real
PassphraseSession never-unlocked. Adds androidx.work:work-testing so the workers
can be driven via TestListenableWorkerBuilder with a custom WorkerFactory (their
extra Hilt-assisted constructor args aren't supported by the default factory).
Closes#226
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
JMR-devandClaude Opus 4.8