Outbox — what happens if you publish offline

If you hit Publish without a network connection (or the upload fails), the post lands in the Outbox queue and shows 'Sending…' on Hub. The app retries with backoff when the network returns. Tap 'Retry' to force it now. If a post fails permanently you can discard it from the same pill. Posts that get stuck on 'Sending…' for longer than 10 minutes now self-recover — on your next app open, AND on every worker tick, any envelope that's been sending too long is flipped to 'Sent' and flagged with a 'stuck-sending recovered — verify on socials' note so you know to double-check the actual social platform. On the backend side, retries are now deduped by (you, network, post_id) for 6 hours, so a re-publish after a timeout will never double-post to the same network.