chore: document new docs.yml configs

fern/products/docs/pages/customization/what-is-docs-yml.mdx

@@ -89,6 +89,11 @@ navbar-links:
   [`layout` configuration](/learn/docs/getting-started/global-configuration#layout-configuration).
 </ParamField>
 
+<ParamField path="settings" type="object" required={false}>
+  Customize the settings of your documentation website. Learn more about the 
+  [`settings` configuration](/learn/docs/getting-started/global-configuration#settings-configuration).
+</ParamField>
+
 <ParamField path="landing-page" type="object" required={false}>
   Creates a landing page for your documentation website. Learn more about the 
   [`landing-page` configuration](/learn/docs/getting-started/global-configuration#landing-page-configuration).
@@ -446,6 +451,51 @@ layout:
   If set to true, the feedback form will not be rendered. This can be overridden on a per-page basis using the [frontmatter](/learn/docs/configuration/page-level-settings#on-page-feedback).
 </ParamField>
 
+## Settings configuration 
+
+```yaml docs.yml
+settings:
+  search-text: "Search the docs..."
+  disable-search: false
+  dark-mode-code: true
+  default-search-filters: true
+  http-snippets: true
+  hide-404-page: true
+  use-javascript-as-typescript: false
+```
+
+<ParamField path="settings.search-text" type="string" required={false} default="Search">
+  The text to display in the searchbar.
+</ParamField>
+
+<ParamField path="settings.disable-search" type="boolean" required={false}>
+  If set to true, the searchbar will be disabled. Use this if you want to use a custom search solution.
+</ParamField>
+
+<ParamField path="settings.dark-mode-code" type="boolean" required={false}>
+  If set to true, the code blocks will be displayed in dark mode, regardless of the selected theme.
+</ParamField>
+
+<ParamField path="settings.default-search-filters" type="boolean" required={false}>
+  By default, search will display results for pages across all products and versions. 
+
+  If set to true, search will display results for pages within the current product and version.
+</ParamField>
+
+<ParamField path="settings.http-snippets" type="boolean" required={false}>
+  If set to true, the HTTP snippets will be displayed in the API Reference.
+</ParamField>
+
+<ParamField path="settings.hide-404-page" type="boolean" required={false}>
+  If set to true, when a user navigates to a page that does not exist, they will be redirected to the home page.
+
+  By default, a 404 page will be displayed.
+</ParamField>
+
+<ParamField path="settings.use-javascript-as-typescript" type="boolean" required={false}>
+  If set to true, the TypeScript snippets will be displayed as JavaScript snippets in the API Reference.
+</ParamField>
+
 ## GitHub configuration
 
 <Tabs>

fern/snippets/seo-metadata-site.mdx

@@ -82,3 +82,9 @@ metadata:
 <ParamField path="metadata.twitter:card" type="string" required={false}>
   The Twitter Card type. Options are `summary`, `summary_large_image`, `app`, or `player`.
 </ParamField>
+
+<ParamField path="metadata.canonical-host" type="string" required={false}>
+  The host of your documentation website. This will be used to set the canonical URL for metadata tags and documents like the sitemap. 
+
+  Defaults to the URL defined in the `instances` configuration.
+</ParamField>