https://open.margincode.dev/2026-11-04 https://open.margincode.dev/demo2026-11-04 https://open.margincode.dev/guides/handoff-between-ai-coding-agents2026-11-04 https://open.margincode.dev/guides/memory-for-coding-agents2026-11-04 https://open.margincode.dev/llms.txt2026-11-04