chore(openspec): archive all completed changes, sync 14 new specs to library

Archived 4 completed OpenSpec changes (2026-04-02):
- phase-3-enterprise (100/100 tasks) — 6 Phase 3 capabilities synced
- devops-documentation (48/48 tasks) — 3 new + 1 merged capability
- bedroom-developer-docs (33/33 tasks) — 4 new capabilities synced
- engineering-docs (superseded by 2026-03-29 archive) — no tasks

Main spec library grows from 21 → 35 capabilities (+14 new):
federation, multi-tenancy, oidc, soc2, w3c-dids, webhooks,
database, operations, system-overview, api-reference, core-concepts,
developer-guides, quick-start + deployment (merged additive requirements)

Active changes: 0 — project board is clear for Phase 4 planning.

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

openspec/changes/archive/2026-04-02-engineering-docs/specs/engineering-overview/spec.md

@@ -0,0 +1,28 @@
+## ADDED Requirements
+
+### Requirement: Company and product overview document
+The system SHALL include a document (`docs/engineering/01-overview.md`) that explains SentryAgent.ai's mission, the AgentIdP product, target users, and why the product exists — providing new engineers with business and product context before they read any technical content.
+
+#### Scenario: Mission and vision covered
+- **WHEN** a new engineer reads 01-overview.md
+- **THEN** they SHALL understand what SentryAgent.ai builds, why it exists, and what problem it solves for AI developers
+
+#### Scenario: AGNTCY alignment explained
+- **WHEN** a new engineer reads 01-overview.md
+- **THEN** they SHALL understand what AGNTCY is, why SentryAgent.ai aligns to it, and what "first-class agent identity" means
+
+#### Scenario: Product features listed
+- **WHEN** a new engineer reads 01-overview.md
+- **THEN** they SHALL see a summary of all product capabilities: agent registry, OAuth 2.0 auth, credential management, audit logs, SDKs, web dashboard, policy engine, and monitoring
+
+#### Scenario: Phase roadmap visible
+- **WHEN** a new engineer reads 01-overview.md
+- **THEN** they SHALL understand which capabilities belong to Phase 1, Phase 2, and Phase 3
+
+#### Scenario: Engineering team structure explained
+- **WHEN** a new engineer reads 01-overview.md
+- **THEN** they SHALL understand the Virtual Engineering Team model (CTO → Architect → Developer → QA) and how Claude operates as the engineering partner
+
+#### Scenario: Free tier limits documented
+- **WHEN** a new engineer reads 01-overview.md
+- **THEN** they SHALL see the free tier limits (100 agents, 10,000 token requests/month, 90-day audit retention, 100 req/min) and understand the product's positioning