A 5e storytelling engine with an LLM DM

Complete phase 6 and add the scenario replay plan master

Phase 6, streaming markdown, is done: the roadmap marks it complete and its plan moves to plans/completed/. The new plan 0009 describes a replay facility that runs a scripted session through the real play loop, so rendering can be reviewed and TUI behavior tested without a live model or network. It lowers the cost of testing the terminal.