docs: commit all Phase 6 documentation updates and OpenSpec archives

- devops docs: 8 files updated for Phase 6 state; field-trial.md added (946-line runbook)
- developer docs: api-reference (50+ endpoints), quick-start, 5 existing guides updated, 5 new guides added
- engineering docs: all 12 files updated (services, architecture, SDK guide, testing, overview)
- OpenSpec archives: phase-7-devops-field-trial, developer-docs-phase6-update, engineering-docs-phase6-update
- VALIDATOR.md + scripts/start-validator.sh: V&V Architect tooling added
- .gitignore: exclude session artifacts, build artifacts, and agent workspaces

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

openspec/changes/archive/developer-docs-phase6-update/proposal.md

@@ -0,0 +1,34 @@
+# OpenSpec Proposal — developer-docs-phase6-update
+
+**Status:** Approved  
+**Proposed:** 2026-04-04  
+**Approved by:** CEO  
+
+## Problem Statement
+
+The developer documentation in `docs/developers/` was written during Phase 2. Phases 3–6 shipped
+analytics, API tiers, AGNTCY compliance, A2A delegation, DID identity, OIDC, webhooks, federation,
+and the marketplace — none of which appear in the developer docs. The API reference covers only
+14 endpoints; the current codebase has ~25+ endpoints. The README contains a "bedroom developers"
+typo. External developers cannot use Phase 3–6 features without documentation.
+
+## Workstreams
+
+### WS1 — api-reference.md
+Update to document all current endpoints with full request/response schemas, auth requirements,
+and error codes. Replace the 14-endpoint Phase 1 reference with the complete Phase 6 surface.
+
+### WS2 — concepts.md
+Add Phase 3–6 concepts: multi-tenancy/organizations, DID identity (did:web), OIDC provider,
+A2A delegation, API tier plans (Free/Pro/Enterprise), and AGNTCY compliance.
+
+### WS3 — quick-start.md
+Update to add org creation as Step 1 (now required before agent registration), and verify all
+endpoint paths match current routes.
+
+### WS4 — guides/
+Revise the 4 existing guides for current endpoint paths and org-scoped requests.
+Add new guides: analytics dashboard, tier management, A2A delegation, webhooks, AGNTCY compliance.
+
+### WS5 — README.md
+Fix "bedroom developers" typo → "developers". Update document index to list all new guides.