feat(ui): default expand tool call results and execution log

Tool call status cards and execution log panel now expand by default
so users can see CoT process and results without clicking.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

langgraph/src/components/ExecutionLogPanel.tsx

@@ -39,7 +39,7 @@ interface ExecutionLogPanelProps {
 }
 
 export function ExecutionLogPanel({ executionLog }: ExecutionLogPanelProps) {
-  const [expanded, setExpanded] = useState(false);
+  const [expanded, setExpanded] = useState(true);
 
   if (!executionLog.length) return null;
 

langgraph/src/components/ToolCallStatus.tsx

@@ -105,7 +105,7 @@ function ToolCallRow({
   globalExpanded,
 }: ToolCallRowProps) {
   // Local state used only when globalExpanded is undefined (single tool or no global toggle)
-  const [localExpanded, setLocalExpanded] = useState(isFailed);
+  const [localExpanded, setLocalExpanded] = useState(true);
   const expanded = globalExpanded !== undefined ? globalExpanded : localExpanded;
   const setExpanded = useCallback((val: boolean | ((v: boolean) => boolean)) => {
     if (globalExpanded === undefined) {
@@ -252,7 +252,7 @@ export default function ToolCallStatus({
   if (!toolCalls.length) return null;
 
   // Global expand/collapse state — only active when there are >= 2 tool calls
-  const [globalExpanded, setGlobalExpanded] = useState<boolean | undefined>(undefined);
+  const [globalExpanded, setGlobalExpanded] = useState<boolean | undefined>(true);
 
   const UI_NAME_MAP: Record<string, string> = {
     kb_search: "knowledge-result",