idea: Add support for additional model file formats (Safetensors, PyTorch, etc.)

[imtuyethan]

Problem Statement

Currently, Jan only supports GGUF format models, requiring users to find or convert models to GGUF before using them with Jan. This creates friction for users who want to use models in their original formats, especially when working with newer models released in formats like safetensors.

Feature Idea

Enable Jan to support additional model file formats:

• Safetensors Support (both fp16 and fp32 variants)
• Implement auto-conversion to GGUF if needed for compatibility?
• PyTorch (.pt, .pth) format support
• ...

[imtuyethan]

Closed as dup: #4254