[JBWortley]

Automatic downloads were failing on Android 14 when Lagrange was in the background. WorkManager tried to start its foreground service and Android rejected it, leaving the durable queue stuck. A cold worker could also mistake a valid saved profile for a signed-out session because it did not restore the stored session before checking authentication.

This keeps manual downloads foregrounded, but runs automatic transfers as ordinary constrained WorkManager jobs. A terminal failure is recorded and the bounded scan continues with the rest of the queue. The planner now uses the current authenticated session when it has one, restores the active profile's saved session when it does not, and retries temporary verification failures instead of asking the user to sign in again.

I installed the exact branch APK on a Sony XQ-CQ44 running Android 14. With Lagrange backgrounded, it completed a 9,701,925-byte PDF in the selected SD-card folder, removed the completed queue entry, and automatically advanced to the next file. I also tested a five-item Article batch with the phone locked and confirmed that transient network interruptions retained the durable queue for retry. There were no Lagrange foreground-service start denials.

The existing periodic planner remains a persistent 24-hour WorkManager job. It survives ordinary process death and reboot, and continues scanning in bounded batches after each download queue drains.

This does not add byte-range resume. Very large single files still depend on WorkManager's normal execution window and retry behavior.

Checks:

• 1,327 JVM tests pass
• Android lint passes
• Android instrumentation tests compile
• Debug APK assembles
• Localization and hardcoded-string checks pass

[van-geaux]

@JBWortley, this looks good to merge. Thanks for the thorough work on the background-download fix!