Implement support for CSF 3

[rwaltenberg]

Is your feature request related to a problem? Please describe.
Currently, Ladle supports Component Story Format (CSF) 2, but a newer version, CSF3, has been released. CSF3 offers several improvements that streamline story creation and maintenance:

• ♻️ Spreadable Story Objects: Facilitate easier story extension and reuse.
• 🌈 Default Render Functions: Reduce boilerplate, making stories more concise.
• 📓 Automatic Titles: Enhance convenience by auto-generating titles.

For more details, refer to their official CSF3 announcement.

Describe the solution you'd like
I propose that Ladle adds support for CSF3. This enhancement would facilitate smoother migrations from Storybook to Ladle and simplify the process of creating and managing stories. Given that CSF3 has been the default in Storybook since version 7, many projects have already adopted this format. Supporting CSF3 in Ladle would make it more accessible to these projects, reducing the friction associated with migration.

Additional Context
Ladle has been recognized for its performance advantages over Storybook, particularly in large-scale projects. Benchmarks indicate that Ladle offers faster startup times and more efficient hot module reloading, enhancing developer productivity. Integrating CSF3 support would combine these performance benefits with the improved ergonomics of the latest story format, providing a compelling reason for teams to adopt Ladle.

Moreover, as the frontend ecosystem continues to evolve, staying current with widely adopted standards like CSF3 ensures that Ladle remains a competitive and modern tool for UI component development.