docs: update docusaurus to v3 (#5625)

* update dependencies

* update onboarding mdx

* fixes for mdx issues

* fixes for mdx compatibility

* resolve mdx errors

* fixes in reference

* fix check errors

* revert change in vale action

* fix node version in action

* fix summary in markdown

www/apps/docs/content/references/services/interfaces/AddRulesDTO.mdx

@@ -22,7 +22,7 @@ The rules to add to a price set.
   },
   {
     "name": "rules",
-    "type": "{ `attribute`: `string`  }[]",
+    "type": "`{ attribute: string  }`[]",
     "description": "The rules to add to a price set. The value of `attribute` is the value of the rule's `rule_attribute` attribute.",
     "optional": false,
     "defaultValue": "",