test: comprehensive CLI tests and GitHub Actions CI workflow

[sairaamv]

Summary

• Rewrites tests/test_main_cli.py from 2 tests to 35, covering:
  • Happy path (exit zero, output messages, report ID, total findings, time taken)
  • Zero findings and nonexistent directory cases
  • --version, --help, scan --help flags
  • All report formats: txt, md, json, all (3 files created), auto-increment filenames
  • AI provider flags: missing credentials errors, ollama no-models error, successful scans
  • AI findings → _llm report file created; no findings → message shown
  • --with-ai, --ai-mode, --personal-only flag behaviour
  • Upload flow: prompt N skips upload, prompt Y calls upload, success URL shown, failure doesn't crash
• Adds .github/workflows/test.yml to run pytest tests/ -v automatically on every PR to dev/main across Python 3.9, 3.11, and 3.12 using uv

Test plan

• uv run --with pytest pytest tests/test_main_cli.py -v — all 35 pass
• Open a test PR and confirm the Actions workflow triggers

Merge order: Can be merged independently; CI workflow will only be useful once PR #7 (refactor) is merged.

🤖 Generated with Claude Code

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