fix(widgets): prevent TabsContainer state reset on data refetch

react-jsx-parser auto-generates random keys on every render, causing
full remounts that reset uncontrolled Tabs to defaultValue. Fix by:
- Adding disableKeyGeneration to preserve React reconciliation
- Memoizing bindings to avoid unnecessary re-parses
- Converting TabsContainer to controlled Tabs with useState
- Validating defaultTab against actual panel values
- Clearing stale parseErrors when template/data changes

packages/widgets/src/custom-api/custom-jsx-display.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import { useCallback, useState } from "react";
+import { useCallback, useEffect, useMemo, useState } from "react";
 import JsxParser from "react-jsx-parser";
 import { Alert, Stack, Text } from "@mantine/core";
 import { IconAlertTriangle } from "@tabler/icons-react";
@@ -19,6 +19,11 @@ export default function CustomJsxDisplay({ data }: { data: Record<string, unknow
   const template = String(data.template ?? "");
   const apiData = data.data;
   const [parseErrors, setParseErrors] = useState<string[]>([]);
+  const bindings = useMemo(() => SAFE_BINDINGS(apiData), [apiData]);
+
+  useEffect(() => {
+    setParseErrors([]);
+  }, [template, bindings]);
 
   const handleError = useCallback((error: Error) => {
     setParseErrors((prev) => appendParseError(prev, error.message));
@@ -39,7 +44,8 @@ export default function CustomJsxDisplay({ data }: { data: Record<string, unknow
       <JsxParser
         jsx={template}
         components={WHITELISTED_COMPONENTS as never}
-        bindings={SAFE_BINDINGS(apiData)}
+        bindings={bindings}
+        disableKeyGeneration
         componentsOnly
         allowUnknownElements={false}
         blacklistedAttrs={[/^on.+/i, /^dangerously/i]}

packages/widgets/src/custom-api/jsx-interactive-components.tsx

@@ -69,9 +69,12 @@ function isTabPanel(child: ReactNode): child is React.ReactElement<TabPanelProps
 export function TabsContainer({ children, defaultTab }: TabsContainerProps) {
   const panels = Children.toArray(children).filter(isTabPanel);
   const firstPanel = panels[0];
+  const panelValues = new Set(panels.map((p) => p.props.value));
+  const initialTab = (defaultTab && panelValues.has(defaultTab) ? defaultTab : firstPanel?.props.value) ?? null;
+  const [activeTab, setActiveTab] = useState<string | null>(initialTab);
 
   return (
-    <Tabs defaultValue={defaultTab ?? firstPanel?.props.value}>
+    <Tabs value={activeTab} onChange={setActiveTab}>
       <Tabs.List>
         {panels.map((panel) => (
           <Tabs.Tab key={panel.props.value} value={panel.props.value}>