docs(roadmap): close out infospace tooling S3 and parent roadmap

All three stages of the infospace tooling roadmap are complete. The Wealth
of Nations / VSM example passes 6/6 viability thresholds on 988 entities,
and composition is demonstrated via the supply-chain-vsm example.

- Parent roadmap (roadmap/infospace-tooling/PLAN.md): header now shows the
  closed status with final validation metrics.
- S3 close-out plan (roadmap/infospace-s3-closeout/PLAN.md): records the
  final task dispositions. C.1–C.6 and C.8 done; C.7 (clean per-chapter
  git history) is deferred indefinitely — the task was cosmetic, its
  prerequisite branch no longer exists, and reconstructing 35 archival
  commits would not change any output files. Rationale documented inline.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

roadmap/infospace-s3-closeout/PLAN.md

@@ -10,6 +10,14 @@ and formally closes the roadmap.
 **Parent roadmap:** `roadmap/infospace-tooling/PLAN.md`
 **Example location:** `examples/infospace-with-history/`
 
+**Status: CLOSED (2026-04-22).** All acceptance criteria except the cosmetic
+per-chapter history (C.7) are met. Final metrics: 988 entities, 988 evaluations,
+6/6 viability thresholds PASS (`per_entity_mean = 3.957`). Tooling work that
+came out of this close-out landed as commits `c0615c2d` (gemini retry,
+unified skip-existing, non-destructive metrics I/O) and `d44a4cd3`
+(`infospace entity` lookup, `evaluate --model-fallback`, `llm-check`
+stale-key advisory, `build_state` type guard).
+
 ### State at workstream open (2026-02-26)
 
 | Item | Status |
@@ -22,6 +30,28 @@ and formally closes the roadmap.
 | 3 missing evaluations | ⏳ Outstanding |
 | 4 follow-up items (commit b055c8d7) | ⏳ Outstanding |
 
+### State at workstream close (2026-04-22)
+
+| Task | Status |
+|------|--------|
+| C.1 Complete 3 missing entity evaluations | ✅ Done (commit f325f89d) |
+| C.2 Run eval-summary and verify viability  | ✅ Done — 6/6 PASS |
+| C.3 Refresh metrics report (988 entities)  | ✅ Done — snapshot `090bb961` |
+| C.4 Document advanced usage patterns        | ✅ Done — `examples/infospace-with-history/docs/advanced-usage.md` |
+| C.5 Composition-examples documentation      | ✅ Done — `docs/composition-guide.md` |
+| C.6 Performance benchmarking note           | ✅ Done — `examples/infospace-with-history/docs/performance-notes.md` |
+| C.7 Clean per-chapter git history           | ⏭️ Deferred indefinitely — see note below |
+| C.8 Formally close S3 roadmap               | ✅ This commit |
+
+**C.7 disposition.** The task assumed a pre-existing `clean-example-history`
+branch with chapters 1–8 already committed; that branch no longer exists in
+the repo. The task is explicitly cosmetic ("does not change output files"),
+and the output files themselves are canonical. Reconstructing a 35-commit
+per-chapter history from scratch would be archaeological rather than useful.
+Closing as "won't do" unless a specific archival need surfaces. If revisited,
+entities can be grouped by their `## Source Chapter` markdown section to
+reconstruct chapter membership.
+
 ---
 
 ## Tasks

roadmap/infospace-tooling/PLAN.md

@@ -1,5 +1,31 @@
 # Viable Infospace Tooling — Roadmap
 
+## Status: CLOSED (2026-04-22)
+
+All three stages complete.
+
+| Stage | Status | Notes |
+|-------|--------|-------|
+| Stage 1 — Platform additions (S1.1–S1.7) | ✅ Done | Entity parser, schema validator, embeddings, graph analysis, eval I/O, batch orchestrator, FCA |
+| Stage 2 — Infospace tooling (S2.1–S2.7)   | ✅ Done | Config model, lifecycle CLI, per-entity eval, collection checks, history, composition, docs |
+| Stage 3 — Example revision (S3.1–S3.5)    | ✅ Done (except cosmetic S3.2) | See `roadmap/infospace-s3-closeout/PLAN.md` |
+
+**Final validation (Wealth of Nations / VSM example, 988 entities):**
+- 988 per-entity evaluations landed
+- Collection checks pass 6/6 viability thresholds (`per_entity_mean = 3.957`
+  against threshold 3.5; `redundancy_ratio = 0.006`; `coverage_ratio = 0.619`;
+  `coherence_components = 0`; `consistency_cycles = 0`;
+  `granularity_entropy = 2.675`)
+- Composition demonstrated via `examples/supply-chain-vsm/`
+- S3.2 (clean per-chapter git history) deferred as cosmetic-only; rationale
+  in the close-out plan
+
+See `roadmap/infospace-s3-closeout/PLAN.md` for the final task-level
+disposition and `examples/infospace-with-history/` for the canonical
+validated example.
+
+---
+
 ## Vision
 
 An **infospace** is a structured, evaluable, composable collection of