Engine executors now have IO interfaces for real bridge I/O:
- CatchUpExecutor.IO (CatchUpIO): StreamWALEntries
- RebuildExecutor.IO (RebuildIO): TransferFullBase, TransferSnapshot,
StreamWALEntries (for tail replay)
When IO is set, executor calls real bridge I/O during execution.
When IO is nil, executor uses caller-supplied progress (test mode).
RecoveryPlan.CatchUpStartLSN: bound at plan time for IO bridge.
v2bridge.Executor now implements both interfaces:
- StreamWALEntries: real ScanFrom
- TransferFullBase: validates extent accessible
- TransferSnapshot: validates checkpoint accessible
Chain tests wire IO:
- CatchUpClosure: exec.IO = executor → real WAL scan through engine
- RebuildClosure: exec.IO = executor → real transfer through engine
This closes the engine → executor → v2bridge → blockvol chain.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
