docs: restructure architecture docs to flowgraph pattern

- Create decisions/ directory with 32 numbered ADRs (ADR-001 through ADR-032)
  extracted from inline DD/SD/ED/SE decision sections
- Create open-questions.md with 16 OQs organized by theme, cross-referenced
  to ADRs, with status tracking (resolved/open)
- Create README.md as architecture index with doc table, ADR table, and
  lifecycle status definitions (draft/reviewed/stable/deprecated)
- Replace inline decision sections in all spec docs with ADR reference tables
- Replace inline open questions with OQ references to centralized tracker
- Update frontmatter: metagraph-module.md, overview.md, sqlite-host.md → reviewed;
  schema-evolution.md and encrypted-data.md remain draft
- DD1-DD10 → ADR-009 through ADR-018
- D1-D8 → ADR-001 through ADR-008
- SD1-SD5 → ADR-019 through ADR-023 (SD5 folded into ADR-006/008)
- ED1-ED5 → ADR-023 through ADR-027
- SE1-SE5 → ADR-028 through ADR-032

docs/architecture/decisions/017-pointer-abstraction-is-forward-looking.md

@@ -0,0 +1,25 @@
+# ADR-017: Pointer abstraction is forward-looking, not v1
+
+## Status
+
+Accepted
+
+## Context
+
+There's a structural analogy between ujsx's `ValuePointer`/`selectNode`/`setNode` and graph node/edge addressing. Typed graph pointers (via JPATH Module or reactive signals) could provide compile-time-safe graph queries.
+
+## Decision
+
+For v1, repository functions use direct key-based addressing (`findNode(graphId, nodeKey)`). Typed pointers are a post-v1 concern. The Module's existence makes typed pointers feasible later because it provides the schema the pointer validates against, but implementing them now adds complexity without clear benefit.
+
+## Consequences
+
+- v1 repository API uses string-based keys for node/edge lookups
+- Attribute access is untyped JSON retrieval (`node.attributes.requestId`)
+- The Module validates attribute shapes, but query paths are strings
+- The pointer abstraction can layer on top of the repository later
+
+## References
+
+- [metagraph-module.md](../metagraph-module.md)
+- [forward-look.md](../forward-look.md)