The recall card could show call_type/trigger_at but not the self-instruction
(additional_context_message) — it was absent from RecallUpdate.to_wire, so
the user couldn't see what future-self was about to do at the scheduled or
fired moment. Extend the wire payload.

- events.RecallUpdate: add `message` field; to_wire emits "message".
- scheduler._publish_recall_update: accept and forward `message`.
- Publish sites carry message=recall.additional_context_message:
  schedule_recall (scheduled) and orchestrator._finalize_recall
  (rescheduled / fired / cancelled). manage_recall cancel/skip omit it
  (no recall object handy; already visible in the prior scheduled card).
- TUI RecallRenderer: preview the message (first line + "(+N lines)",
  capped at 80) on a `msg:` body line when present.
- Tests: RecallUpdate.to_wire carries message (defaults None); renderer
  preview (single/multiline/truncate/empty) and scheduled-card renders it.

Co-Authored-By: Claude <noreply@anthropic.com>

The scheduler/orchestrator already push RecallUpdate (wire type
"recall_update") for the schedule_recall lifecycle, but the TUI had no
mapping or renderer — every event fell to the unknown-event catch-all and
rendered as a raw dict dump. Wire it into a dedicated card.

- chat_model: add a "recall" ChatItem kind and a recall_update branch
  (before the catch-all) that keeps the wire fields in meta.
- chat_panel _item_msg: reconstruct {"type": "recall_update", **meta}
  for a recall item so the registry sees it.
- renderers/recall.py: new RecallRenderer — a compact, color-coded card
  per action (⏰ scheduled/info, ▶ fired·resuming/accent, ✕ cancelled/error,
  ↻ skipped/warning, ↻ rescheduled/info) showing call_type and a trimmed
  trigger_at. Registered before the generic renderers.
- tests: 10 tests covering accepts, each action's title/border color,
  trigger formatting, empty body, chat_model mapping, and _item_msg
  round-trip.

MVP only — the self-instruction (additional_context_message) is not on the
wire, so it remains visible in the schedule_recall tool-call card above;
extending RecallUpdate.to_wire to carry it is a follow-up.

Co-Authored-By: Claude <noreply@anthropic.com>