[WOOTAX-294] Ban bundled React imports in the store notices tree

Nothing stopped a bundled React import from coming back into these files, and
the unit tests cannot catch it: under Jest the host React and the bundled React
are the same instance, so an element built with the wrong one still looks right.

Restrict the react import in this tree instead, and record the constraint next
to the code it applies to, along with the dependency list the entry relies on.

Author: Abdalsalaam

.eslintrc.js

@@ -23,4 +23,29 @@ Object.assign( calypsoLintConfig.globals, {
     global: true,
 });
 
+// The store notices bundle is rendered by the React that WordPress provides, inside the
+// Cart/Checkout blocks. React 19 rejects elements created by an older React runtime, so
+// importing the plugin's bundled React here would break the block cart and checkout.
+// Everything in this tree must build its elements with window.wp.element instead.
+calypsoLintConfig.overrides = [
+    ...( calypsoLintConfig.overrides || [] ),
+    {
+        files: [ 'client/store-notices.js', 'client/components/store/notices/*.js' ],
+        rules: {
+            'no-restricted-imports': [
+                'error',
+                {
+                    paths: [
+                        {
+                            name: 'react',
+                            message:
+                                'This tree is rendered by the host React: build elements with window.wp.element instead. See client/store-notices.js.',
+                        },
+                    ],
+                },
+            ],
+        },
+    },
+];
+
 module.exports = useE2EEsLintConfig( calypsoLintConfig );

client/store-notices.js

@@ -3,6 +3,9 @@
  */
 import { StoreNotices } from 'components/store/notices';
 
+// Every global read here is a script dependency: keep this list in sync with the
+// dependencies declared in WooCommerceBlocksIntegration::register_script(), which is
+// what guarantees these are loaded before this script runs.
 const { registerPlugin } = window.wp.plugins;
 const { createElement } = window.wp.element;
 const { ExperimentalOrderMeta } = window.wc.blocksCheckout;
@@ -13,11 +16,13 @@ const { ExperimentalOrderMeta } = window.wc.blocksCheckout;
  * Elements here must be created with the WordPress-provided React
  * (window.wp.element), not the plugin's bundled React: this tree is rendered
  * by the host React inside the Cart/Checkout blocks, and React 19 rejects
- * elements created by an older React runtime.
+ * elements created by an older React runtime. This is why the slot fill is
+ * built with createElement rather than the JSX used in the doc below.
  *
  * @see https://github.com/woocommerce/woocommerce/blob/a7231863c014a95602f5932f702171465fa7bcf2/docs/cart-and-checkout-blocks/available-slot-fills.md?plain=1#L53
+ *   ExperimentalOrderMeta slot fill reference.
  *
- * @return {Object} The plugin content.
+ * @return {Object} The plugin content, as a host React element.
  */
 const render = () => {
 	return createElement( ExperimentalOrderMeta, null, createElement( StoreNotices ) );