feat: TypeScript presets/plugins should expose Options typing (#5456)

* each TS plugin should export option types + preset export option / themeConfig types + remove TS typechecking for the bootstrap theme

* each TS plugin should export option types + preset export option / themeConfig types + remove TS typechecking for the bootstrap theme

* fix remaining TS errors

* fix remaining TS errors

* TS fix

* Add JSDoc type annotations to init templates and TS docs

* missing title char

website/docs/typescript-support.md

@@ -42,7 +42,7 @@ It is **not possible** to use a TypeScript config file in Docusaurus, unless you
 
 We recommend using [JSDoc type annotations](https://www.typescriptlang.org/docs/handbook/jsdoc-supported-types.html):
 
-```js title="docusaurus.config.js
+```js title="docusaurus.config.js"
 // highlight-start
 /** @type {import('@docusaurus/types').Plugin} */
 // highlight-end
@@ -55,15 +55,49 @@ function MyPlugin(context, options) {
 // highlight-start
 /** @type {import('@docusaurus/types').DocusaurusConfig} */
 // highlight-end
-const config = {
+(module.exports = {
   title: 'Docusaurus',
   tagline: 'Build optimized websites quickly, focus on your content',
   organizationName: 'facebook',
   projectName: 'docusaurus',
   plugins: [MyPlugin],
-};
-
-module.exports = config;
+  presets: [
+    [
+      '@docusaurus/preset-classic',
+      // highlight-start
+      /** @type {import('@docusaurus/preset-classic').Options} */
+      // highlight-end
+      ({
+        docs: {
+          path: 'docs',
+          sidebarPath: 'sidebars.js',
+        },
+        blog: {
+          path: 'blog',
+          postsPerPage: 5,
+        },
+      }),
+    ],
+  ],
+  themeConfig:
+    // highlight-start
+    /** @type {import('@docusaurus/preset-classic').ThemeConfig} */
+    // highlight-end
+    ({
+      colorMode: {
+        defaultMode: 'dark',
+      },
+      navbar: {
+        hideOnScroll: true,
+        title: 'Docusaurus',
+        logo: {
+          alt: 'Docusaurus Logo',
+          src: 'img/docusaurus.svg',
+          srcDark: 'img/docusaurus_keytar.svg',
+        },
+      },
+    }),
+});
 ```
 
 :::tip