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/specify-payload-truncation.md

@@ -0,0 +1,37 @@
+---
+id: specify-payload-truncation
+name: Specify Call Graph Payload Truncation Details
+status: completed
+depends_on: [document-payload-redaction]
+scope: narrow
+risk: low
+impact: isolated
+level: implementation
+---
+
+## Description
+
+W18: The truncation strategy says "truncate payloads larger than 10KB" but doesn't specify: when truncation happens (on write? after call completes?), what `preview` contains (first N bytes? N characters?), whether 10KB is configurable, or how object storage reference URLs are structured.
+
+Specify: (a) truncation happens on write to DB (in-flight calls have full payloads); (b) `preview` is the first 1024 bytes of the JSON-serialized payload; (c) threshold is configurable per operation type or via hub config; (d) defer object storage details but add a placeholder section.
+
+## Acceptance Criteria
+
+- [ ] `call-graph.md` specifies truncation timing: on DB write, not in-flight
+- [ ] `preview` field defined: first 1024 bytes of JSON-serialized payload
+- [ ] 10KB threshold documented as configurable (hub config or per-operation-type)
+- [ ] Placeholder section for object storage reference (deferred)
+- [ ] Cross-reference to redaction strategy (this task depends on W08 resolution)
+
+## References
+
+- docs/reviews/storage-architecture-review-2026-04-21.md#W18
+- docs/architecture/storage/call-graph.md:30
+
+## Notes
+
+> To be filled by implementation agent
+
+## Summary
+
+> To be filled on completion