feat: auto-generate Nuxt ofetch GraphQL client for quick start (#13)

* feat: auto-generate Nuxt ofetch GraphQL client for quick start

- Add automatic generation of ofetch.ts for Nuxt projects
- Generate ofetch client only once with customization comments
- Rename server-type-generation.ts to type-generation.ts for clarity
- Improve client codegen configuration for better type safety
- Support framework-specific client generation patterns

The generated ofetch.ts provides a ready-to-use GraphQL client
using Nuxt's $fetch and useRequestHeaders for SSR compatibility.

* fix: ensure newline at end of file in ofetch.ts

Author: productdevbook