Add zod schema validation (#1198)

* add zod schema validation

* update pageUrlFormat config name

* add trailing slash support to config

examples/framework-react/astro.config.mjs

@@ -1,15 +1,13 @@
-export default {
-  // projectRoot: '.',     // Where to resolve all URLs relative to. Useful if you have a monorepo project.
-  // pages: './src/pages', // Path to Astro components, pages, and data
-  // dist: './dist',       // When running `astro build`, path to final static output
-  // public: './public',   // A folder of static files Astro will copy to the root. Useful for favicons, images, and other files that don’t need processing.
-  buildOptions: {
-    // site: 'http://example.com',  // Your public domain, e.g.: https://my-site.dev/. Used to generate sitemaps and canonical URLs.
-    // sitemap: true,      // Generate sitemap (set to "false" to disable)
-  },
-  devOptions: {
-    // port: 3000,         // The port to run the dev server on.
-    // tailwindConfig: '', // Path to tailwind.config.js if used, e.g. './tailwind.config.js'
-  },
+// Full Astro Configuration API Documentation:
+// https://docs.astro.build/reference/configuration-reference
+
+// @type-check enabled!
+// VSCode and other TypeScript-enabled text editors will provide auto-completion,
+// helpful tooltips, and warnings if your exported object is invalid.
+// You can disable this by removing "@ts-check" and `@type` comments below.
+
+// @ts-check
+export default /** @type {import('astro').AstroUserConfig} */ ({
+  // Enable the React renderer to support React JSX components.
   renderers: ['@astrojs/renderer-react'],
-};
+});