docs: fix build errors + update medusa docs link (#8550)

* docs: update medusa docs link

* fix @medusajs/icon version

* fix user guide build

* fix build error

www/apps/api-reference/package.json

@@ -15,7 +15,7 @@
   "dependencies": {
     "@mdx-js/loader": "^3.0.0",
     "@mdx-js/react": "^3.0.0",
-    "@medusajs/icons": "^1.2.0",
+    "@medusajs/icons": "preview",
     "@medusajs/ui": "^3.0.0",
     "@next/mdx": "14.2.3",
     "@readme/openapi-parser": "^2.5.0",