chore(log): add AGENT_LOG entry for archetype scaffold v2

https://claude.ai/code/session_01SbYsmmbPf9YQuYbHZN52Zh

Author: AdaWorldAPI

.claude/board/AGENT_LOG.md

@@ -0,0 +1,12 @@
+# AGENT_LOG
+
+Append-only log of agent sessions. Prepend new entries at the top.
+
+---
+
+## 2026-04-24T16:30 — Archetype scaffold v2 (sonnet, claude/archetype-crate-scaffold)
+
+**D-ids:** DU-2.1..2.6
+**Commit:** `816a7c0`
+**Tests:** 12 pass
+**Outcome:** Shipped `lance-graph-archetype` crate scaffold: Component + Processor traits (Arrow-backed), World meta-state with tick/fork/at_tick stubs, CommandBroker FIFO queue, ArchetypeError (thiserror). Added to root workspace members. No compile errors; 12 unit tests green.