Recommended setup - Keep your paymail online for reachabili…

Recommended setup
- Keep your paymail online for reachability and backward compatibility.
- Add an auto-sweeper that:
- Tags all paymail-sourced deposits as “Legacy (bridged).”
- Immediately (or per policy) sweeps to the intended BKDS context UTXO.
- Avoids mixing unrelated contexts in a single sweep.
- Prefer BRC100-native requests for counterparties who support them. Offer paymail only as a fallback during migration.