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

tests/test_commit_linter.py

@@ -0,0 +1,118 @@
+"""Unit tests for the Commit Linter (Conventional Commits)."""
+
+import sys
+import os
+import tempfile
+
+import pytest
+
+sys.path.insert(0, os.path.join(
+    os.path.dirname(__file__), "..", "engineering", "changelog-generator", "scripts"
+))
+from commit_linter import lint, CONVENTIONAL_RE, lines_from_file, CLIError
+
+
+class TestConventionalCommitRegex:
+    """Test the regex pattern against various commit message formats."""
+
+    @pytest.mark.parametrize("msg", [
+        "feat: add user authentication",
+        "fix: resolve null pointer in parser",
+        "docs: update API documentation",
+        "refactor: simplify login flow",
+        "test: add integration tests for auth",
+        "build: upgrade webpack to v5",
+        "ci: add GitHub Actions workflow",
+        "chore: update dependencies",
+        "perf: optimize database queries",
+        "security: patch XSS vulnerability",
+        "deprecated: mark v1 API as deprecated",
+        "remove: drop legacy payment module",
+    ])
+    def test_valid_types(self, msg):
+        assert CONVENTIONAL_RE.match(msg) is not None
+
+    @pytest.mark.parametrize("msg", [
+        "feat(auth): add OAuth2 support",
+        "fix(parser/html): handle malformed tags",
+        "docs(api.v2): update endpoint docs",
+    ])
+    def test_valid_scopes(self, msg):
+        assert CONVENTIONAL_RE.match(msg) is not None
+
+    def test_breaking_change_marker(self):
+        assert CONVENTIONAL_RE.match("feat!: redesign API") is not None
+        assert CONVENTIONAL_RE.match("feat(api)!: breaking change") is not None
+
+    @pytest.mark.parametrize("msg", [
+        "Update readme",
+        "Fixed the bug",
+        "WIP: something",
+        "FEAT: uppercase type",
+        "feat:missing space",
+        "feat : extra space before colon",
+        "",
+        "merge: not a valid type",
+    ])
+    def test_invalid_messages(self, msg):
+        assert CONVENTIONAL_RE.match(msg) is None
+
+
+class TestLint:
+    def test_all_valid(self):
+        lines = [
+            "feat: add login",
+            "fix: resolve crash",
+            "docs: update README",
+        ]
+        report = lint(lines)
+        assert report.total == 3
+        assert report.valid == 3
+        assert report.invalid == 0
+        assert report.violations == []
+
+    def test_mixed_valid_invalid(self):
+        lines = [
+            "feat: add login",
+            "Updated the readme",
+            "fix: resolve crash",
+        ]
+        report = lint(lines)
+        assert report.total == 3
+        assert report.valid == 2
+        assert report.invalid == 1
+        assert "line 2" in report.violations[0]
+
+    def test_all_invalid(self):
+        lines = ["bad commit", "another bad one"]
+        report = lint(lines)
+        assert report.valid == 0
+        assert report.invalid == 2
+
+    def test_empty_input(self):
+        report = lint([])
+        assert report.total == 0
+        assert report.valid == 0
+        assert report.invalid == 0
+
+
+class TestLinesFromFile:
+    def test_reads_file(self):
+        with tempfile.NamedTemporaryFile(mode="w", suffix=".txt", delete=False) as f:
+            f.write("feat: add feature\nfix: fix bug\n")
+            f.flush()
+            lines = lines_from_file(f.name)
+        os.unlink(f.name)
+        assert lines == ["feat: add feature", "fix: fix bug"]
+
+    def test_skips_blank_lines(self):
+        with tempfile.NamedTemporaryFile(mode="w", suffix=".txt", delete=False) as f:
+            f.write("feat: add feature\n\n\nfix: fix bug\n")
+            f.flush()
+            lines = lines_from_file(f.name)
+        os.unlink(f.name)
+        assert len(lines) == 2
+
+    def test_nonexistent_file_raises(self):
+        with pytest.raises(CLIError, match="Failed reading"):
+            lines_from_file("/nonexistent/path.txt")