Setup repo: migrate architecture specs, code stubs, and tasks from alkhub_ts

Copy architecture docs, ADRs, storage domain specs, research, reviews,
and 56 storage architecture tasks from the alkhub_ts monorepo. Adapt for
standalone @alkdev/hub repo structure (src/ not packages/hub/).

Sanitize all sensitive information:
- Replace private IPs (10.0.0.1) with localhost defaults
- Remove internal server hostnames (dev1, ns528096)
- Replace /workspace/ private paths with npm package references
- Remove hardcoded credentials from examples
- Rewrite infrastructure.md without private network details

Add Deno project scaffolding: deno.json (pinned deps), .gitignore,
AGENTS.md, entry point. Migrate existing code stubs (crypto, config
types, logger) with updated import paths.

tasks/architecture/storage/resolve-audit-logs-ownerid-cascade.md

@@ -0,0 +1,41 @@
+---
+id: resolve-audit-logs-ownerid-cascade
+name: Resolve audit_logs.ownerId NOT NULL + SET NULL contradiction
+status: completed
+depends_on: []
+scope: narrow
+risk: critical
+impact: component
+level: implementation
+---
+
+## Description
+
+`audit_logs.ownerId` is declared `text NOT NULL` in `identity.md:112` but has `onDelete: SET NULL` in `table-reference.md:71`. PostgreSQL will reject the DELETE because it cannot nullify a NOT NULL column.
+
+## Decision (D1)
+
+**Change cascade to RESTRICT**. Audit trails should prevent account deletion — this follows the "audit/traceability data: RESTRICT" cascade pattern. Accounts with audit entries cannot be hard-deleted. Account deactivation (via the new `status` column, D5) is the path for handling departed users.
+
+## Acceptance Criteria
+
+- [ ] `audit_logs.ownerId` cascade is changed from `SET NULL` to `RESTRICT` in `table-reference.md:71`
+- [ ] `identity.md` documents that `ownerId` is NOT NULL with RESTRICT cascade, explaining that accounts with audit entries cannot be deleted
+- [ ] The rationale is documented: "audit trails must preserve accountability; RESTRICT prevents data integrity violations and ensures audit completeness"
+- [ ] Note about operational implication: "accounts with audit entries are deactivated (status: suspended/deactivated) rather than deleted"
+- [ ] Cross-reference to D5 (account deactivation via status column)
+
+## References
+
+- docs/reviews/storage-architecture-review-2026-04-21.md#C01
+- docs/decisions/storage-spec-phase1-resolutions.md#D1
+- docs/architecture/storage/identity.md:112
+- docs/architecture/storage/table-reference.md:71
+
+## Notes
+
+> To be filled by implementation agent
+
+## Summary
+
+> To be filled on completion