Add tests for string intersection type handling and fix tsconfig

Author: Who-is-PS

fixtures/components/string-intersection/code-editor/index.tsx

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+// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+import * as React from 'react';
+
+export namespace CodeEditorProps {
+  // This simulates the pattern used in the code editor where we want:
+  // 1. Autocomplete for known language literals
+  // 2. Allow custom string values
+  export type Language = 'javascript' | 'html' | 'ruby' | 'python' | 'java' | (string & { _?: undefined });
+}
+
+export interface CodeEditorProps {
+  /**
+   * Specifies the programming language.
+   */
+  language: CodeEditorProps.Language;
+}
+
+export default function CodeEditor({ language }: CodeEditorProps) {
+  return <div data-language={language}>Code Editor</div>;
+}

fixtures/components/string-intersection/tsconfig.json

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+{
+  "extends": "../tsconfig.json",
+  "include": ["./**/*.tsx"]
+}