Kernel-Olympics

Change a system prompt in src/router.py and keep PROMPT_VERSION, prompts/CHANGELOG.md, and data/prompt_changelog.json in sync. Use when editing any string in SYSTEM_PROMPTS, or when asked to "bump the prompt version" or "add a changelog entry".

Run the CUDA→ROCm/HIP porting pipeline over one or more .cu kernels and read the result honestly. Use when asked to "port a kernel", "run the pipeline", "try it on <file>.cu", or to reproduce a run.