[Obs AI Assistant] replace EuiErrorBoundary with KibanaErrorBoundary (elastic#229710)

Replaces `EuiErrorBoundary` with using `core.rendering.addContext()`.


https://github.com/elastic/kibana/blob/main/src/core/packages/rendering/browser/README.mdx

I tested this by throwing an error in the feedback buttons and the AI
Assistant button itself and confirmed they are caught by the
`KibanaErrorBoundary`.

---------

Co-authored-by: kibanamachine <[email protected]>

Author: neptunian

x-pack/solutions/observability/plugins/observability_ai_assistant_app/public/utils/shared_providers.tsx

@@ -4,7 +4,6 @@
  * 2.0; you may not use this file except in compliance with the Elastic License
  * 2.0.
  */
-import { EuiErrorBoundary } from '@elastic/eui';
 import type { CoreStart, CoreTheme } from '@kbn/core/public';
 import { KibanaContextProvider } from '@kbn/kibana-react-plugin/public';
 import { KibanaThemeProvider } from '@kbn/react-kibana-context-theme';
@@ -31,23 +30,21 @@ export function SharedProviders({
     return { theme$ };
   }, [theme$]);
 
-  return (
-    <EuiErrorBoundary>
-      <KibanaThemeProvider theme={theme}>
-        <KibanaContextProvider
-          services={{
-            ...coreStart,
-            ...pluginsStart,
-            plugins: {
-              start: pluginsStart,
-            },
-          }}
-        >
-          <RedirectAppLinks coreStart={coreStart}>
-            <coreStart.i18n.Context>{children}</coreStart.i18n.Context>
-          </RedirectAppLinks>
-        </KibanaContextProvider>
-      </KibanaThemeProvider>
-    </EuiErrorBoundary>
+  return coreStart.rendering.addContext(
+    <KibanaThemeProvider theme={theme}>
+      <KibanaContextProvider
+        services={{
+          ...coreStart,
+          ...pluginsStart,
+          plugins: {
+            start: pluginsStart,
+          },
+        }}
+      >
+        <RedirectAppLinks coreStart={coreStart}>
+          <coreStart.i18n.Context>{children}</coreStart.i18n.Context>
+        </RedirectAppLinks>
+      </KibanaContextProvider>
+    </KibanaThemeProvider>
   );
 }