v0.3

• Breaking change: rename generate_text(prompt: String) -> String to generate_text_simple(prompt: String) -> String, you may also add 2 empty string argument (generate_text(prompt, "", "")) to achieve a similar result.
• Unfortunately, embedding does not work with vulkan backend at the moment, now change to cpu build and let's wait for the upstream fix
• Add GDEmbedding node for sentence embedding computation
• Add GDLlava node for multimodal model
• Introduce multiple run_* methods for GDLlama, GDEmbedding, and GDLlava to run computation in background,