Review findings from ds-review-bot: closing the loading picker now
aborts the scan through the AbortSignal both query methods accept, a
signal-ignoring backend's late settlement is dropped by a staleness
check, one catch spans listing and projection so a projection failure
closes the overlay instead of stranding the loading placeholder,
setCandidates clears a stale still-loading error, and the batch
comment no longer overstates the win as scaling with session count.