Postgres engine: streams — StreamHandle (auto-commit publishes + best-effort pg_notify wake, ASC reads with the extent guard, monotone offsets, pool-connection trim) and the durable subscribe receiver (async bridge, wake-driven re-drains, reconnect gap-heal, shutdown-only terminal close, stateless idle wake runtime for the sync save) (task pg-engine-streams)

alkstore-postgres/src/tx.rs

@@ -79,6 +79,7 @@ use crate::resolution::{
 };
 use crate::schema::{QualifiedTable, tables};
 use crate::seam::{pg_error, pool_error};
+use crate::stream::stream_events_from_rows;
 
 /// The notification payload boundary (the contract's pinned limit —
 /// client-side checked, typed before any round trip; the predicate
@@ -637,27 +638,7 @@ fn job_from_row(row: &tokio_postgres::Row) -> Result<Job> {
     ))
 }
 
-/// Decode a read page into the contract's [`StreamEvent`] values (the
-/// core constructor's `from_row`). Malformed rows map to `Error::Codec`.
-fn stream_events_from_rows(
-    rows: &[tokio_postgres::Row],
-    stream: String,
-) -> Result<Vec<StreamEvent>> {
-    let mut out = Vec::with_capacity(rows.len());
-    for row in rows {
-        let key: Option<String> = row
-            .try_get(1)
-            .map_err(|e| Error::Codec(format!("stream row key must be text: {e}")))?;
-        let payload: Option<Vec<u8>> = row
-            .try_get(2)
-            .map_err(|e| Error::Codec(format!("stream row payload must be bytea: {e}")))?;
-        out.push(StreamEvent::from_row(
-            row.get(0),
-            stream.clone(),
-            key,
-            payload.unwrap_or_default(),
-            row.get(3),
-        ));
-    }
-    Ok(out)
-}
+// The stream-page decode (`stream_events_from_rows`) lives in
+// `stream.rs` — the one decode owner the tx reads and the auto-commit
+// reads share (the `stream` field mapping and the `Codec` posture
+// guard live once; ADR-012 §2's one-owner rule).