docs(GOO-33): comprehensive documentation sprint

Create/update all Sprint 6 documentation:
- CHANGELOG.md: document GOO-33 and recent audit findings
- CONTRIBUTING.md: add branching, PR, commit conventions
- docs/ci-cd.md: GitHub Actions pipeline documentation
- docs/onboarding.md: developer setup & onboarding guide
- docs/mcp-servers.md: MCP servers API documentation
- docs/PROJECT_TRACKER.md: mark GOO-33 as in_progress
- docs/QA_TRACKER.md: test status and verification plans

Curate audit reports (reduce ~103 → 12 canonical files):
- Keep canonical audit reports with descriptive index
- Archive obsolete/duplicate audit exploration files

Acceptance Criteria:
- [x] QA_TRACKER.md exists with current test status
- [x] CHANGELOG.md updated to today
- [x] PROJECT_TRACKER.md reflects current sprint status
- [x] CI/CD pipeline documented
- [x] CONTRIBUTING.md has branching, PR, commit conventions
- [x] docs/audits/ reduced to canonical reports

Co-Authored-By: Paperclip <noreply@paperclip.ing>

docs/audits/CANONICAL_INDEX.md

@@ -0,0 +1,49 @@
+# Audit Files Index
+
+**Last Updated:** 2026-04-22
+
+This folder contains curated canonical audit reports. Temporary or duplicate audit files have been archived.
+
+## Canonical Audit Reports
+
+| File | Date | Purpose | Status |
+|------|------|---------|--------|
+| **AUDIT_INDEX.md** | 2026-04-22 | Main audit findings index | Current |
+| **AUDIT_SUMMARY.md** | 2026-04-22 | Executive audit summary | Current |
+| **COMPREHENSIVE_AUDIT_2026-04-12.md** | 2026-04-12 | Full CEO audit report (8 parts) | Reference |
+| **API_AUDIT_REPORT.md** | 2026-04-19 | Backend API audit (handlers, errors) | Current |
+| **WEB_AUDIT_SUMMARY.md** | 2026-04-19 | Frontend Web audit (components, tests) | Current |
+| **TEST_COVERAGE_AUDIT.md** | 2026-04-19 | Unit test coverage analysis | Current |
+| **INFRASTRUCTURE_RUNBOOK.md** | 2026-04-19 | Infrastructure setup & troubleshooting | Current |
+| **MCP_QUICK_REFERENCE.md** | 2026-04-19 | MCP servers documentation | Current |
+| **CODE_QUALITY_AUDIT.md** | 2026-04-19 | Code quality metrics & patterns | Current |
+| **AUDIT_DETAILED_CHECKLIST.md** | 2026-04-19 | Detailed verification checklist | Reference |
+
+---
+
+## How to Use These Reports
+
+### For New Team Members
+1. Start with **AUDIT_SUMMARY.md** (5 min read)
+2. Then **WEB_AUDIT_SUMMARY.md** + **API_AUDIT_REPORT.md** (10 min each)
+3. Reference **INFRASTRUCTURE_RUNBOOK.md** for setup
+
+### For Architecture Decisions
+- Read **COMPREHENSIVE_AUDIT_2026-04-12.md** (full context)
+- Check **CODE_QUALITY_AUDIT.md** for patterns
+
+### For Testing & Coverage
+- **TEST_COVERAGE_AUDIT.md** — current coverage gaps
+- **AUDIT_DETAILED_CHECKLIST.md** — what needs testing
+
+### For DevOps & Setup
+- **INFRASTRUCTURE_RUNBOOK.md** — deployment & troubleshooting
+
+---
+
+## Archived Files
+
+Old audit exploration files have been moved to `.archive/` for reference but are not actively maintained. If you need historical context, check the archive.
+
+**Curation date:** 2026-04-22
+**Curator:** Doc Bot (GOO-33)