Module engine 

The replication engine: reader task, applier loop, and reconnect policy.

Guarantees:

• Events are applied in the order the source produced them.
• A source transaction is applied atomically together with its checkpoint.
• WAL positions are acknowledged only after the corresponding target commit returned.
• Redelivered transactions (after crash/reconnect) are skipped by LSN comparison.
• Memory held by undelivered events is bounded by the channel limits.

Structs

AckPosition

Position the reader reports to the server. Only acked is ever reported as flushed.

ApplyOutcome

Functions

run_apply_loop

Runs one connected stream until cancellation or error.

run_replication

Reconnecting driver: opens a stream and a sink, runs the apply loop, and on transient failures reloads the checkpoint from the sink (the source of truth) and reconnects.