Add the Ergasterion: Hickey, Fowler, Parnas architecture workshop

Pre-implementation architecture inspection for one proposed design at a
time, distinct from the Court's rulebook-level governance (which already
carries its own "Academy" self-identity in court.agent.md) and from
al-review's post-hoc diff review. Wired into al-complexity's HIGH-tier
route as the actual human architecture sign-off.

- Hickey: what does this model, and what's complected?
- Fowler: does this pay for itself, or borrow against the next change?
- Parnas: is what's likely to change hidden behind a stable interface?
  (proactive counterpart to Titus Winters' Hyrum's Law check in al-review)

custom/setup/templates/al-complexity.agent.md

@@ -129,9 +129,13 @@ MEDIUM
 - Short spec -> TDD (tests FIRST, then code) -> bcquality.agent.md review.
 
 HIGH
-- Architecture clarify first (CURABIS-ARCH-010) -> spec -> TDD -> bcquality.agent.md review,
-  with al-triage.agent.md on standby. Flag for explicit human architecture sign-off before
-  implementation starts.
+- If the requirement itself is still ambiguous, Columbo resolves that first
+  (CURABIS-ARCH-010) — this is not the Ergasterion's job. Then convene the
+  Ergasterion (`ergasterion.agent.md` — Hickey, Fowler, Parnas) on the proposed
+  design -> spec -> TDD -> bcquality.agent.md review, with al-triage.agent.md
+  on standby. The Ergasterion's ruling (PROCEED / PROCEED WITH CHANGES /
+  RECONSIDER), plus Michael's decision on it, IS the human architecture
+  sign-off — not a step a developer can wave off by saying "looks fine to me."
 
 ## Action - advisory protocol