fix: cast merged config+options object to fix nuxt client typecheck

Co-authored-by: mrlubos <12529395+mrlubos@users.noreply.github.com>

Author: Copilot

packages/openapi-ts/src/plugins/@hey-api/client-nuxt/bundle/client.ts

@@ -184,7 +184,8 @@ export const createClient = (config: Config = {}): Client => {
     });
   };
 
-  const _buildUrl: Client['buildUrl'] = (options) => buildUrl({ ..._config, ...options });
+  const _buildUrl: Client['buildUrl'] = (options) =>
+    buildUrl({ ..._config, ...options } as typeof options);
 
   return {
     buildUrl: _buildUrl,