v0.7.0

• Tracebacks are now trimmed by frame rather than by character count. Application frames are always kept, and library frames fill the remaining budget nearest the error. Previously a deep Django ORM stack could consume the entire budget, leaving no application code in the explanation prompt at all.
• The tail-slice fallback no longer depends on sys.exc_info(), which under a real ASGI server may not have been populated in the worker thread.
• README: an Evaluation section reporting measured results for whether RAG improves explanations, a clearer account of language support, and the redundant Example section removed.