v4: get an error "Invalid key: Expected "address" but received undefined" if field is object in valibot schema

### What happened? I use vee-validate and valibot, dependencies in package.json: ```json "dependencies": { "@vee-validate/valibot": "^4.15.1", "valibot": "^1.2.0", "vee-validate": "^4.15.1", "vue": "^3.5.27", }, ``` If valibot's schema contains object field an "Invalid key: Expected "address" but received undefined" error is thrown. I think this happens because only for valibot integration meta.initialValues don't set with empty object's literals. I found this bug when I updated valibot from 1.0.0.beta-3 to 1.2.0, but when I rolled back, the error continued to be thrown ### Reproduction steps 1. Create any valibot schema with object's field 2. Do not set initial values in useForm ### Version Vue.js 3.x and vee-validate 4.x ### What browsers are you seeing the problem on? - [x] Firefox - [x] Chrome - [ ] Safari - [ ] Microsoft Edge ### Demo link https://stackblitz.com/edit/vitejs-vite-st3i7srf?file=src%2FApp.vue ### Code of Conduct - [x] I agree to follow this project's [Code of Conduct](CONDUCT.md)