fix: reconnect stale Lingma IPC sessions

internal/service/service_test.go

@@ -0,0 +1,25 @@
+package service
+
+import (
+	"errors"
+	"testing"
+)
+
+func TestIsRecoverableIPCError(t *testing.T) {
+	cases := []error{
+		errors.New("write websocket frame: write tcp 127.0.0.1:64954->127.0.0.1:36510: use of closed network connection"),
+		errors.New("broken pipe"),
+		errors.New("Lingma IPC notification stream closed"),
+	}
+	for _, err := range cases {
+		if !isRecoverableIPCError(err) {
+			t.Fatalf("expected recoverable error: %v", err)
+		}
+	}
+}
+
+func TestIsRecoverableIPCErrorIgnoresModelErrors(t *testing.T) {
+	if isRecoverableIPCError(errors.New("timed out while waiting for Lingma IPC to finish responding")) {
+		t.Fatal("timeout should not be treated as an immediate reconnect retry")
+	}
+}