feat(tests): add comprehensive test suite with 1493 tests across 4 phases

Phase 1 - Foundation:
- Add pytest, pyproject.toml, requirements-dev.txt
- 593 smoke tests (324 syntax + 269 argparse --help) for all Python scripts
- Harden CI: remove || true from compileall, expand to all 9 directories, add pytest step

Phase 2 - Calculator unit tests:
- RICE prioritizer: formula, prioritization, portfolio analysis, roadmap
- DCF valuation: WACC, cash flow projections, terminal value, sensitivity
- Financial ratios: profitability, liquidity, leverage, efficiency, valuation
- Campaign ROI: metrics, benchmarks, portfolio summary
- Funnel analyzer: stage metrics, bottleneck detection, segment comparison
- OKR tracker: numeric/percentage/milestone/boolean KR scoring, status

Phase 3 - Parser and compliance tests:
- SEO checker: HTML parsing, scoring, heading hierarchy, alt text, word count
- Commit linter: conventional commit regex, lint report, file input
- GDPR compliance: pattern detection, file scanning, project analysis

Phase 4 - Integration tests:
- 671 skill integrity tests: frontmatter, H1 headings, scripts dirs, references

Bug fixes found by tests:
- Fix duplicate --reason argparse arg in document_version_control.py

https://claude.ai/code/session_01MsVmZoAsPvLv7rAGDBGTbL

.github/workflows/ci-quality-gate.yml

@@ -50,6 +50,7 @@ jobs:
         run: |
           python -m pip install --upgrade pip
           pip install yamllint==1.35.1 check-jsonschema==0.28.4 safety==3.2.4
+          pip install -r requirements-dev.txt
 
       - name: Set up Node.js
         uses: actions/setup-node@v4
@@ -71,9 +72,13 @@ jobs:
             ! -name "smart-sync.yml" \
             -exec check-jsonschema --builtin-schema github-workflows {} + || true
 
-      - name: Python syntax check
+      - name: Python syntax check (blocking)
         run: |
-          python -m compileall marketing-skill product-team c-level-advisor engineering-team ra-qm-team || true
+          python -m compileall marketing-skill product-team c-level-advisor engineering-team ra-qm-team engineering business-growth finance project-management scripts
+
+      - name: Run test suite
+        run: |
+          python -m pytest tests/ --tb=short -q
 
       - name: Safety dependency audit (requirements*.txt)
         run: |