Migrate-to-seed submits z_mergetoaddress -> an async opid, then only persists the resolved
txid once the op completes. An app-close during Sweeping (opid submitted, txid not yet
resolved) dropped the opid and resumed at the re-sweep gate, silently losing the tx.
Now the opid is persisted and re-tracked on resume. If the daemon forgot it (restart —
its op queue is in-memory only), the existing poller flags it stale and the callback falls
back to the dismissable Sweep gate; it can never hang (a thrown RPC aborts the poll, so a
stale classification only comes from a *successful* poll that omits the opid).
- New seed_migration_sweep_opid setting; adopted atomically with clearing any prior txid in
the SAME settings.save(), and only once the submit succeeds — so a failed "Sweep remaining"
re-sweep keeps the already-mined first sweep's Confirming context, and txid/opid are never
both authoritative (resume checks txid first; torn-write safe).
- Resume routing extracted to a pure, unit-tested helper
(data/seed_migration_resume.h::decideSeedMigrationResume): txid -> Confirming; opid AND
connected -> re-track (Sweeping); else -> the dismissable Sweep gate. The connectivity gate
keeps a disconnected resume out of the buttonless Sweeping spinner.
- Shared makeSweepCompletionCallback(resumed): success -> Confirming; resumed-stale -> Sweep
gate (re-fetch balance + "may have already completed" copy); fresh-fail -> Error.
Fund safety unchanged: adopt still gated on legacy balance ~0 AND sweep tx mined; legacy
wallet.dat only ever moved to a never-deleted timestamped .bak.
Reviewed in two adversarial rounds (design + implementation) per the migration-code mandate;
both safety facts (no fund loss, no hang) held, and the resume-UX traps they surfaced are
fixed. Build-clean; ctest 1/1 (adds testSeedMigrationResume). See docs/wallet-hardening.md.
*** Still requires a live mainnet interrupted-sweep run before release (human gate). ***
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>