docs: fix broken links utility + uncaught broken links (#12637)

* fix broken links

* update broken links utility

* add missing payment evens

* generate llms

* fix segment link

www/apps/user-guide/next.config.mjs

@@ -33,6 +33,10 @@ const withMDX = mdx({
               projectPath: path.resolve("..", "resources"),
               hasGeneratedSlugs: true,
             },
+            api: {
+              projectPath: path.resolve("..", "api-reference"),
+              skipSlugValidation: true,
+            },
           },
         },
       ],