Address review on the event-taxonomy PR:
- ui-stdio built its session-id→agent-id label map only from live
`agent/created` events, so an agent registered before the UI fiber
installed — the pre-created `main` agent, or any agent surviving an HMR
reload of just this fiber — was missed and its turns rendered the raw
session id instead of `[main turn N]`. Seed the map from
`ctx.agents.list()` at install, then keep it live. Regression test proven
red without the seed.
- The agent event-domain doc still listed "the turn boundaries" among the
TRANSIENT `agent/*` emits, contradicting the rule ten lines below that a
turn/step boundary is a durable `session/event`, not an `agent/*` mirror.
Tianyi Cui
1e87b6fea4