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.

.gitignore

@@ -0,0 +1,38 @@
+# Dependencies
+node_modules/
+
+# Deno
+.deno/
+
+# Environment and secrets
+.env
+.env.*
+.alkhub/
+*.key
+*.pem
+
+# Build artifacts
+dist/
+.target/
+
+# IDE
+.vscode/
+.idea/
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Test artifacts
+coverage/
+
+# Local dev config (never commit secrets)
+dev-db.json
+test-config.json
+test-master-key.txt
+
+# Drizzle
+drizzle/meta/
+
+# Worktrees
+.worktrees/