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/document-jsonb-column-boundaries.md

@@ -0,0 +1,37 @@
+---
+id: document-jsonb-column-boundaries
+name: Document JSONB Column Boundaries (metadata vs data)
+status: completed
+depends_on: []
+scope: narrow
+risk: medium
+impact: component
+level: implementation
+---
+
+## Description
+
+W01: The `commonCols.metadata` and per-table `data` JSONB columns overlap with no documented boundary. `api_keys` stores `scopes`/`resources`/`tags` inside `metadata`; `accounts` has both `data` (preferences, avatar) and `metadata` (arbitrary) with overlapping purposes. An implementer cannot determine which column to use for what.
+
+Define and document the boundary: `data` holds structured domain-specific data with known TypeScript types; `metadata` holds opaque key-value pairs for subsystem use with a namespacing convention (e.g., `_keypal.scopes`).
+
+## Acceptance Criteria
+
+- [ ] `README.md` documents the boundary between `commonCols.metadata` and per-table `data` columns
+- [ ] Namespacing convention for `metadata` is specified (e.g., `_subsystem.key`)
+- [ ] Each table that has both columns lists what belongs in each (`identity.md` for `accounts`, `api_keys`)
+- [ ] Update `keypal` usage note: `api_keys.metadata._keypal.scopes` pattern documented
+
+## References
+
+- docs/reviews/storage-architecture-review-2026-04-21.md#W01
+- docs/architecture/storage/README.md:73
+- docs/architecture/storage/identity.md:85-88, :23
+
+## Notes
+
+> To be filled by implementation agent
+
+## Summary
+
+> To be filled on completion