docs(vscode-extension): the Export to React sample keeps its declared h1 node (objectui#11515)

`h1` is a declared type (`HtmlElementSchema`, objectui#8499), and
`check-doc-component-types.test.ts` pins it in this very sample as the
registered replacement for `heading`. With the constant annotated, the
`h1` sample compiles against the built packages today and with
objectui#11466 applied (measured with tsc and with check:doc-snippets on
both trees), so the `text` / `variant: 'h1'` rewrite the card proposed is
not needed and is reverted. The compile pin's documented sample follows.

Claude-Session: https://claude.ai/code/session_01XvhGmGAP79ZB8swnkapxPC
Co-authored-by: Claude <noreply@anthropic.com>

Author: claude

.changeset/11515-vscode-export-react-annotation.md

@@ -8,4 +8,4 @@ Unannotated, every `type` in the constant widened to `string`. A `SchemaRenderer
 
 `SchemaNode` was the annotation first proposed, and it does not fit: it also admits `number` and `boolean`, which the prop leaves out, so every generated file was refused at its one JSX line.
 
-The compile pin gains a leg against the real prop type, read from `SchemaRenderer.tsx`, with a positive control. The two documented copies of the preamble (`DESIGN.md` and the docs page) follow it, and the docs page's sample authors a `text` node with its `h1` variant.
+The compile pin gains a leg against the real prop type, read from `SchemaRenderer.tsx`, with a positive control. The two documented copies of the preamble (`DESIGN.md` and the docs page) follow it. The docs page's sample keeps its `h1` node: `h1` is a declared type (`HtmlElementSchema`), and the annotated sample compiles both today and with objectui#11466 applied.

content/docs/utilities/vscode-extension.mdx

@@ -108,9 +108,8 @@ const schema: SchemaRendererProps['schema'] = {
   "className": "p-4",
   "children": [
     {
-      "type": "text",
-      "variant": "h1",
-      "content": "Hello World"
+      "type": "h1",
+      "children": "Hello World"
     }
   ]
 };

packages/vscode-extension/src/__tests__/export-to-react-compiles.test.ts

@@ -463,12 +463,16 @@ describe('Export to React — the documented mirrors of the preamble (objectui#7
 const REACT_SCHEMA_RENDERER = join(REPO_ROOT, 'packages/react/src/SchemaRenderer.tsx');
 const TYPES_SOURCE_ENTRY = join(REPO_ROOT, 'packages/types/src/index.ts');
 
-/** The documented sample (`content/docs/utilities/vscode-extension.mdx`), in declared types. */
+/**
+ * The documented sample (`content/docs/utilities/vscode-extension.mdx`). Both
+ * of its types are declared: `div`, and `h1`, one of the HTML passthrough tags
+ * `HtmlElementSchema` declares (objectui#8499).
+ */
 const DOC_SAMPLE_SCHEMA = JSON.stringify(
   {
     type: 'div',
     className: 'p-4',
-    children: [{ type: 'text', variant: 'h1', content: 'Hello World' }],
+    children: [{ type: 'h1', children: 'Hello World' }],
   },
   null,
   2