- Add REASONING_PREFIXES for Big 10 model families (Qwen, Llama3, DeepSeek, etc.)
- Add REASONING_STOP_TOKENS for stopping reasoning generation
- Add force_reasoning_prompt() to construct prompts ending with thought tags
- Add extract_reasoning() to parse reasoning from responses
- Add format_for_raw_completion() and create_reasoning_prompt() convenience functions
- This enables 'token hijacking' to force models to start with reasoning