[Pages] Document wildcards before a file extension in _routes.json

src/content/docs/pages/functions/routing.mdx

@@ -160,7 +160,7 @@ This file will include three different properties:
 
 :::note
 
-Wildcards match any number of path segments (slashes). For example, `/users/*` will match everything after the`/users/` path.
+Wildcards match any number of path segments (slashes). For example, `/users/*` will match everything after the `/users/` path.
 
 :::
 
@@ -188,6 +188,16 @@ Below is another example of a `_routes.json` file. Any route inside the `/build`
 }
 ```
 
+A wildcard can also come before a file extension, and it matches at any depth. Use this when static files and Function routes share a path, such as an API that serves pre-rendered `.json` files beside routes a Function answers. With this `_routes.json`, `/api/users/1.json` and `/api/users/1/posts.json` are served as static assets without invoking the Function, while `/api/users/1` and `/api/search` invoke it:
+
+```json
+{
+	"version": 1,
+	"include": ["/api/*"],
+	"exclude": ["/api/*.json"]
+}
+```
+
 ## Fail open / closed
 
 If on the Workers Free plan, you can configure how Pages behaves when your daily free tier allowance of Pages Functions requests is exhausted. If, for example, you are performing authentication checks or other critical functionality in your Pages Functions, you may wish to disable your Pages project when the allowance is exhausted.