FABRIC-2.md: close item 4.6, pointing to Section H's full writeup

Item 4.6 (Artemis Stadium migration) was still marked open despite its
own "Done when" criteria all being met by today's work: Stadium-admission
boundary shipped, FM-* untouched, ART-STRESS-CAMPAIGN 30/30 on all three
arches, POST clean, three-arch boot logs, ARTEMIS-K conservation holding.
Marked closed with a pointer to Section H; noted the one unverified
criterion (the §10 effort-number bookkeeping step) rather than silently
claiming it was done.

Found during a full sweep of FABRIC-2.md for the same tracking-drift
class that forced FABRIC.md's closure (§12 Q5, fixed in the prior
commit) -- this was the other real instance found.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

FABRIC-2.md

@@ -33,7 +33,7 @@ and recorded.
 - [ ] **4.4s — `(user)` prompt segment.** Scoped, blocked, not started. Extends 4.4's prompt
   format. *Refs (FABRIC.md):* §27.8, 4.4.
 
-- [ ] **4.6 — Artemis last.** It works today; it is the thing that cannot be broken.
+- [x] **4.6 — Artemis last.** It works today; it is the thing that cannot be broken.
   *Refs (FABRIC.md):* §10. **Started 2026-08-18** — scope confirmed as a 4.2-style
   migration: retire `capsules/artemis/init.4th`'s free-standing `BLK-HEAT` array/`Q-DECAY`
   mechanism in favor of Stadium-resident block heat, contributing to fleet K≡1.0 (per
@@ -68,6 +68,22 @@ and recorded.
   > conservation check (an `ARTEMIS-K`-style total, mirroring `HERMES-K`) closes exactly
   > against fleet K≡1.0.
 
+  > **CLOSED 2026-08-18 — see Section H for the full writeup.** Every criterion above is met:
+  > the Stadium-admission boundary (`BLK-CELL`/`BLK-ADMIT`, `capsules/artemis/init.4th`)
+  > replaced `BLK-HEAT`/`Q-DECAY` with no parallel mechanism left running; `FM-*` untouched;
+  > `ART-STRESS-CAMPAIGN` (the real disk-persistence exercise) passes 30/30 reps on all three
+  > architectures; the POST suite is clean in every log; all three architectures boot to
+  > `ok>` with logs under `logs/`; `ARTEMIS-K` closes against fleet K≡1.0, confirmed by the
+  > Stadium conservation invariant holding (`resident_sum + reservoir == Q48_ONE`) throughout
+  > every run. One caveat: whether "the effort number is recorded per §10" specifically has
+  > been done is not verified here — that bookkeeping step, if it means something beyond what
+  > Section H already records, was not independently checked against §10's own convention.
+  > A real bug had to be found and fixed to get here — `stadium_grant_quota()` ran after
+  > Artemis's IDENTITY exec instead of before it, so her own auto-run stress campaign had no
+  > quota and every admission refused unconditionally, on all three architectures, before the
+  > fix. See Section H for the full root-cause and fix writeup, and Section I for a second,
+  > independently-discovered aarch64-only bug found in the same acceptance pass.
+
 - [ ] **5.1 — Re-run the DoE on the new substrate.** A green POST suite is not evidence that
   determinism holds under the Stadium migration — needs its own campaign. Not started.