tokenizer_config: inline the gemma-4 chat template (ships as separate chat_template.jinja upstream, which swift-transformers does not read; without it prompts raw-encode and generation degenerates to turn markers)
tokenizer_config: inline the gemma-4 chat template (ships as separate chat_template.jinja upstream, which swift-transformers does not read; without it prompts raw-encode and generation degenerates to turn markers)