fix(coding): keep optimistic identity across snapshots

src/stores/coding-conversations.ts

@@ -160,6 +160,22 @@ function withoutReconciledRequests(
   );
 }
 
+function withReconciledOptimisticNodeIds(
+  snapshot: ConversationSnapshot,
+  requests: Record<string, CodingPromptRequestState> | undefined,
+): ConversationSnapshot {
+  if (!requests) return snapshot;
+  let changed = false;
+  const nodes = snapshot.nodes.map((node) => {
+    if (node.kind !== 'message' || !node.clientRequestId) return node;
+    const nodeId = requests[node.clientRequestId]?.nodeId;
+    if (!nodeId || node.id === nodeId) return node;
+    changed = true;
+    return { ...node, id: nodeId };
+  });
+  return changed ? { ...snapshot, nodes } : snapshot;
+}
+
 function optimisticNode(
   nodeId: string,
   clientRequestId: string,
@@ -601,12 +617,16 @@ export function createCodingConversationStore(
         if (!current.reducer.invalidation && snapshotIsOlder(current.reducer.snapshot, snapshot)) {
           return state;
         }
+        const reconciledSnapshot = withReconciledOptimisticNodeIds(
+          snapshot,
+          state.requestsByConversationId[event.conversationId],
+        );
         const requests = withoutReconciledRequests(
           state.requestsByConversationId[event.conversationId],
-          snapshot,
+          reconciledSnapshot,
         );
         const reducer = withUnreconciledOptimisticNodes(
-          replaceConversationSnapshot(current.reducer, snapshot),
+          replaceConversationSnapshot(current.reducer, reconciledSnapshot),
           requests,
         );
         const entry: CodingConversationEntry = {