Transcript Incremental Projection

Nucleic-Session: 0FFD007B-0696-4517-9429-129C7B0FD5AC
Co-authored-by: Nucleic <[email protected]>

NucleicRemote/NucleicRemote/Models/RemoteStore.swift

@@ -639,20 +639,23 @@ final class RemoteStore: ObservableObject {
             guard let self, hostID == self.openSessionHostID, snap.summary.sessionID == self.openSessionID else { return }
             // Merge, don't replace: a fresh open merges into an empty transcript (the tail window),
             // while a reconnect's warm-resubscribe delta appends to the history already on screen
-            // instead of truncating it to the host's 200-event tail.
+            // instead of truncating it to the host's 200-event tail. Drain the streaming buffer
+            // first so the seq-dedup merge sees the full stream (a buffered event the snapshot
+            // also carries would otherwise be re-appended as a duplicate after the merge).
+            self.drainPendingOpenEvents()
             self.openEvents = Self.mergedEvents(self.openEvents, snap.recentEvents)
             self.openApprovals = snap.pendingApprovals
             self.persistOpenTranscript()
         }
         cb.openEvents = { [weak self] batch in
             guard let self, hostID == self.openSessionHostID, batch.sessionID == self.openSessionID else { return }
-            self.openEvents.append(contentsOf: batch.events)
-            self.persistOpenTranscript()
+            self.enqueueOpenEvents(batch.events)
         }
         cb.openBackfill = { [weak self] batch in
             guard let self, hostID == self.openSessionHostID, batch.sessionID == self.openSessionID else { return }
             // Full-history backfill precedes what's on screen — merge by seq so it slots in above the
-            // tail rather than appending out of order.
+            // tail rather than appending out of order. Drain first (same reason as openSnapshot).
+            self.drainPendingOpenEvents()
             self.openEvents = Self.mergedEvents(self.openEvents, batch.events)
             self.persistOpenTranscript()
         }