Session Sync Repair

Nucleic-Session: 0C7BC346-0002-4533-ADDD-3B4C92E58527
Co-authored-by: Nucleic <[email protected]>

NucleicRemote/NucleicRemote/Models/HostConnection.swift

@@ -476,12 +476,17 @@ final class HostConnection {
             callbacks.didUpdate()
         case .snapshot(let snapshot):
             guard snapshot.summary.sessionID == openSessionID else { break }
-            seenSeq = Set(snapshot.recentEvents.map(\.seq))
+            // A snapshot may be a fresh open (tail window) or a warm-resubscribe delta; either way
+            // union its seqs into the dedup set and advance the cursor. RemoteStore merges the events
+            // into the transcript rather than replacing, so an existing transcript isn't truncated.
+            seenSeq.formUnion(snapshot.recentEvents.map(\.seq))
+            if let maxSeq = snapshot.recentEvents.map(\.seq).max() { openMaxSeq = max(openMaxSeq ?? 0, maxSeq) }
             callbacks.openSnapshot(snapshot)
         case .events(let batch):
             guard batch.sessionID == openSessionID else { break }
             let fresh = batch.events.filter { !seenSeq.contains($0.seq) }
             for e in fresh { seenSeq.insert(e.seq) }
+            if let maxSeq = batch.events.map(\.seq).max() { openMaxSeq = max(openMaxSeq ?? 0, maxSeq) }
             if !fresh.isEmpty { callbacks.openEvents(EventBatch(sessionID: batch.sessionID, events: fresh)) }
         case .approvalRequested(let req):
             let title = sessions.first { $0.sessionID == req.sessionID }?.title ?? "Approval"