Architect storage around SQLite+Honker: remove PG, add multi-tenant identity, scoping

Reorient @alkdev/storage around a single SQLite database host with Honker
for pub/sub, event streams, and task queues. PostgreSQL is removed as a
target (ADR-038), eliminating dual schema maintenance and infrastructure
complexity. Honker provides DB + pubsub + queues in one .db file (ADR-039).

Add system/tenant DB model (ADR-040): identity tables in system.db, all
graph data in tenant-{orgId}.db files. Identity tables move from the hub
into storage (ADR-041). Scoping columns (ownerId, projectId) added to
graphs table (ADR-042). Graph types get scope (system/tenant/user) to
protect infrastructure schemas (ADR-043).

Define Drizzle-Honker session adapter (ADR-044): ~100-line adapter enabling
Drizzle typed queries and Honker pubsub/queue on a single connection with
transactional consistency.

Resolve OQ-03, OQ-04, OQ-19, OQ-21, OQ-22, OQ-23, OQ-24. Add new
open questions OQ-26 through OQ-29 for Honker integration specifics.

New docs: honker-integration.md (adapter, event patterns, migration).
Scrub all PG/jsonb/libsql references from existing spec docs.

docs/architecture/schema-evolution.md

@@ -1,6 +1,6 @@
 ---
-status: reviewed
-last_updated: 2026-05-30
+status: draft
+last_updated: 2026-05-31
 ---
 
 # Schema Evolution
@@ -28,10 +28,10 @@ data to fit new schema shapes.
 Two distinct domains of JSON values are involved:
 
 - **Schemas-as-JSON**: The TypeBox schema objects stored in `node_types.schema`
-  and `edge_types.schema` columns. `Value.Diff`/`Value.Patch` operate on these
+  and `edge_types.schema` columns (text with JSON mode in SQLite). `Value.Diff`/`Value.Patch` operate on these
   (detecting schema changes, updating stored schemas).
 - **Data-as-JSON**: The node/edge attribute values stored in `nodes.attributes`
-  and `edges.attributes` columns. `Value.Cast`/`Value.Check` operate on these
+  and `edges.attributes` columns (text with JSON mode in SQLite). `Value.Cast`/`Value.Check` operate on these
   (migrating data to fit new schemas, verifying compatibility).
 
 This is not a migration framework. It's the observation that the existing
@@ -104,7 +104,7 @@ stream and storage. That's a post-v1 concern.
 
 TypeBox schemas are JSON Schema objects — plain JSON values. The current
 `node_types.schema` and `edge_types.schema` columns store them as JSON text
-(SQLite) or jsonb (PG). This means `Value.Diff` can diff schemas themselves.
+in SQLite. This means `Value.Diff` can diff schemas themselves.
 
 ### Detecting Schema Changes