quak backup retries failed requests for longer (closes #165)

src/retry.ts exports UNATTENDED_RETRY_OPTIONS beside the unchanged
default: 10 attempts, a 1 s base delay and a 60 s cap, so a request that
keeps failing waits at most 243 s before it gives up. bin/quak.ts loads
the backup's session with them, so its refresh, ML data and downloads
all use them; every other command keeps the default. What is retried
and the backoff formula are unchanged.

Model: opus-5-5

src/index.ts

@@ -27,6 +27,7 @@ export {
     isRetryable,
     isSafeToReplay,
     resolveRetryOptions,
+    UNATTENDED_RETRY_OPTIONS,
     withRetry,
     type ResolvedRetryOptions,
     type RetryOptions,