run.py — Chronicle cut-point test

agent@1 STUB → place_order@1 LIVE ★ → agent@2 LIVE

scenario.set_mode("gated")
session.load_trace("fixtures/traces/trade-notional/")
session.enable_replay(
    ReplayPlan().stub("agent", 1).live("place_order", 1).live("agent", 2)
)

No LLM calls. Agent plan from fixture; tool runs gated code.