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>

VALIDATOR.md

@@ -0,0 +1,52 @@
+#!/bin/bash
+# =============================================================================
+# SentryAgent.ai — Start V&V Architect (Lead Validator)
+# =============================================================================
+# Launches an independent Claude Code instance as the Lead Validator.
+# This agent verifies the CTO's work against the PRD/OpenSpec.
+#
+# Usage:
+#   ./scripts/start-validator.sh
+# =============================================================================
+
+set -e
+
+PROJECT_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+VALIDATOR_WORKSPACE="$PROJECT_ROOT/.validator-workspace"
+VALIDATOR_PROMPT="$PROJECT_ROOT/VALIDATOR.md"
+
+echo "=============================================="
+echo "  SentryAgent.ai — Starting V&V Architect Agent"
+echo "=============================================="
+echo ""
+echo "  Project:      $PROJECT_ROOT"
+echo "  Workspace:    $VALIDATOR_WORKSPACE"
+echo "  Role Config:  $VALIDATOR_PROMPT"
+echo ""
+echo "  The V&V Architect will:"
+echo "  1. Audit Code against OpenSpec PRD"
+echo "  2. Enforce DRY Principles"
+echo "  3. Log Issues for CTO Resolution"
+echo "  4. Maintain Local Fail-Safe Ledger"
+echo ""
+echo "=============================================="
+
+# Ensure the Validator Workspace and Local Ledger exist
+mkdir -p "$VALIDATOR_WORKSPACE/.openspec/vv_audit"
+
+# Verify the Validator Persona file exists (from Part 1 of instructions)
+if [ ! -f "$VALIDATOR_PROMPT" ]; then
+  echo "ERROR: VALIDATOR.md not found at $VALIDATOR_PROMPT"
+  echo "Please ensure you have created the System Instruction file."
+  exit 1
+fi
+
+# Synchronize the latest CLAUDE.md to the validator workspace if needed
+if [ -f "$PROJECT_ROOT/CLAUDE.md" ]; then
+    cp "$PROJECT_ROOT/CLAUDE.md" "$VALIDATOR_WORKSPACE/CLAUDE.md"
+fi
+
+# Launch Claude Code as an independent Auditor
+cd "$VALIDATOR_WORKSPACE"
+exec claude --system-prompt-file "$VALIDATOR_PROMPT"
+