Record architecture decisions: thin git plane, live default, upgrades

D1 thin dir+git with shard-wiki then kontextual upgrade path; D2 defer
asset-store; D3 NetKingdom authz consolidation; D4 outline explode/implode
and live-by-default includes with pin as exception.

docs/architecture/spike-checklist.md

@@ -150,32 +150,23 @@ Scoring legend for each spike: **Pass** / **Partial** / **Fail** / **Skip** with
 
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-## Spike 8 — Cross-option decision workshop
+## Spike 8 — Decision workshop → **mostly closed 2026-08-13**
 
-**Owner:** founder + implementers  
-**Depends on:** Spikes 1–6 results  
+**Recorded in ArchitectureBlueprint §0 (D1–D4):**
 
-- [ ] Fill scorecard (below).
-- [ ] Choose primary content plane for stage 1 + migration path.
-- [ ] Choose asset strategy (in-kontextual vs extract vs folder-only).
-- [ ] File ADR-0003 (page model + SoR) and ADR-0004 (content plane).
-- [ ] Update `docs/capability/model-v0.yaml` feature wording if PageOps replaces Forgejo-centric features.
+| Item | Decision |
+|------|----------|
+| Content plane start | **A** thin dir + git |
+| Upgrades | → shard-wiki → kontextual (supported) |
+| asset-store | **Later** |
+| Authz ownership | **NetKingdom consolidation** (avoid parallel PolicyGateway fiefdom) |
+| Structure UX | Outline **explode/implode**; **live** default; pin exception |
 
-### Scorecard (1–5, higher better)
+Remaining workshop work:
 
-| Criterion | A thin store | B shard-wiki | C kontextual |
-|-----------|:------------:|:------------:|:------------:|
-| Markdown export fidelity | | | |
-| Stage-1 speed | | | |
-| Structure tax (inverse) | | | |
-| Copy/transfer naturalness | | | |
-| Visual/blob readiness | | | |
-| NetKingdom/authz fit | | | |
-| Multi-shard / federation later | | | |
-| Multi-format / ECM later | | | |
-| Railiance operability | | | |
-| Aligns with fleet layers | | | |
-| **Total** | | | |
+- [ ] File ADR-0003 / ADR-0004 reflecting D1–D4.
+- [ ] Sketch export/import round-trip notes for B and C upgrades (feasibility only).
+- [ ] Explode/implode UX prototype on thin tree (Spike 2 + markitect).
 
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