v1.5.0 — max_tokens Fix, Binary Cleanup

v1.5.0\n\n### Fixed\n- Increased max_tokens from 1024 to 4096 for reasoning models (DeepSeek V4 Flash, etc.) — reasoning traces were consuming the token budget, leaving empty responses\n- Stop tracking pre-built binary files bl-dingtalk and bl-telegram in git\n\n### Docs\n- Added session_context.md for project context tracking\n- Updated CHANGELOG through v1.5.0