Avoid shell usage in dependency checker

[bsbodden]

Summary

• Replace curl via subprocess.run(..., shell=True) with urllib.request
• Refactor the dependency checker into small testable functions
• Add a regression test that rejects shell=True

Closes #5

Tests

• uv run pytest tests/test_check_deps_script.py -q
• uv run ruff check .

[github-actions]

✅ MFCQI Score: 0.87 → (±0.000)

➡️ Previous: 0.87

Code quality meets the minimum threshold (0.70).

[github-actions]

✅ MFCQI Score: 0.87 → (±0.000)

➡️ Previous: 0.87

Code quality meets the minimum threshold (0.70).

[github-actions]

✅ Code Quality Report

Metric	Score	Status
MFCQI Score	0.8710511435045868	✅ Good
Test Coverage	82%	✅ Good
Security Issues	0	✅ Clean

Quality Gates

• MFCQI Score: ✅ Minimum 0.75 (Current: 0.8710511435045868)
• Test Coverage: ✅ Minimum 80% (Current: 82%)
• Security: ✅ Zero vulnerabilities (Current: 0)

🎉 All quality gates passed! This PR maintains high code quality standards.

📊 View detailed MFCQI breakdown

Run mfcqi analyze src/mfcqi locally to see detailed metrics breakdown.

[github-actions]

✅ MFCQI Score: 0.87 → (±0.000)

➡️ Previous: 0.87

Code quality meets the minimum threshold (0.70).

[github-actions]

✅ Code Quality Report

Metric	Score	Status
MFCQI Score	0.8715710274260666	✅ Good
Test Coverage	81%	✅ Good
Security Issues	0	✅ Clean

Quality Gates

• MFCQI Score: ✅ Minimum 0.75 (Current: 0.8715710274260666)
• Test Coverage: ✅ Minimum 80% (Current: 81%)
• Security: ✅ Zero vulnerabilities (Current: 0)

🎉 All quality gates passed! This PR maintains high code quality standards.

📊 View detailed MFCQI breakdown

Run mfcqi analyze src/mfcqi locally to see detailed metrics breakdown.