Python analysis fixes: multi-line signatures and test-file secrets
Two Python correctness fixes. Files using multi-line (Black-formatted) function or block signatures are no longer misreported as syntax errors, and test files no longer have their score penalised for fixture credentials.
- Fixed: a Python def/class/if/for/with header that wraps across multiple lines (e.g. a long Black-formatted signature) was being flagged as a syntax error, scoring the file 0 and skipping all analysis. These files now analyse normally.
- Fixed: the suspicious-name secret heuristic no longer fires in test files (test_*.py, *_test.go, *.test.ts, tests/, __tests__/, conftest.py, and similar), so fixture credentials like password="secret123" no longer reduce the score. Real provider token formats (AWS, Stripe, GitHub, and more) are still detected everywhere, including tests.