fix: improve event stream reconnect reliability

Recover stalled event streams without dropping the session
Wait briefly for reconnection before showing connection lost errors
Persist Electron server logs for easier disconnect debugging

packages/ui/src/sync/session-actions.ts

@@ -55,11 +55,30 @@ function dir() {
 }
 
 function connectionLostError(): Error {
-  const reason = useConfigStore.getState().lastDisconnectReason
-  const suffix = reason ? ` (${reason})` : " (never connected)"
+  const { hasEverConnected, lastDisconnectReason } = useConfigStore.getState()
+  const suffix = lastDisconnectReason
+    ? ` (${lastDisconnectReason})`
+    : hasEverConnected
+      ? ""
+      : " (never connected)"
   return new Error(`Connection lost${suffix}. Please wait for reconnection.`)
 }
 
+// Wait briefly for the pipeline to re-establish connection before failing a
+// send. Transient reconnects (heartbeat race, WS→SSE fallback, brief network
+// blip) otherwise surface as a hard "Connection lost" toast even though the
+// pipeline recovers within a second. Poll isConnected at 100ms intervals.
+const CONNECTION_GRACE_MS = 2000
+export async function waitForConnectionOrThrow(): Promise<void> {
+  if (useConfigStore.getState().isConnected) return
+  const deadline = Date.now() + CONNECTION_GRACE_MS
+  while (Date.now() < deadline) {
+    await new Promise((resolve) => setTimeout(resolve, 100))
+    if (useConfigStore.getState().isConnected) return
+  }
+  throw connectionLostError()
+}
+
 function getSessionDirectory(sessionId: string): string | undefined {
   return useSessionUIStore.getState().getDirectoryForSession(sessionId) || dir()
 }
@@ -332,9 +351,7 @@ export async function optimisticSend(input: {
     throw new Error("Optimistic refs not set — is useSync() mounted?")
   }
 
-  if (!useConfigStore.getState().isConnected) {
-    throw connectionLostError()
-  }
+  await waitForConnectionOrThrow()
 
   const store = dirStore()
   const messageID = ascendingId("msg")
@@ -419,9 +436,7 @@ export async function respondToPermission(
   requestId: string,
   response: "once" | "always" | "reject",
 ): Promise<void> {
-  if (!useConfigStore.getState().isConnected) {
-    throw connectionLostError()
-  }
+  await waitForConnectionOrThrow()
   const result = await getRequestReplyClient("permission", sessionId, requestId).permission.reply({
     requestID: requestId,
     reply: response,
@@ -435,9 +450,7 @@ export async function dismissPermission(
   sessionId: string,
   requestId: string,
 ): Promise<void> {
-  if (!useConfigStore.getState().isConnected) {
-    throw connectionLostError()
-  }
+  await waitForConnectionOrThrow()
   const result = await getRequestReplyClient("permission", sessionId, requestId).permission.reply({
     requestID: requestId,
     reply: "reject",
@@ -456,9 +469,7 @@ export async function respondToQuestion(
   requestId: string,
   answers: string[] | string[][],
 ): Promise<void> {
-  if (!useConfigStore.getState().isConnected) {
-    throw connectionLostError()
-  }
+  await waitForConnectionOrThrow()
   const result = await getRequestReplyClient("question", sessionId, requestId).question.reply({
     requestID: requestId,
     answers: answers as Array<Array<string>>,
@@ -472,9 +483,7 @@ export async function rejectQuestion(
   sessionId: string,
   requestId: string,
 ): Promise<void> {
-  if (!useConfigStore.getState().isConnected) {
-    throw connectionLostError()
-  }
+  await waitForConnectionOrThrow()
   const result = await getRequestReplyClient("question", sessionId, requestId).question.reject({
     requestID: requestId,
   })