fix: tolerate log handlers without baseFilename (pytest compat)

[afatihakpolat]

Closes #131

Bug

BusKill.init crashed under pytest with AttributeError: '_LiveLoggingNullHandler' object has no attribute 'baseFilename' at src/packages/buskill/init.py:227, because pytest replaces root handlers with its own (no baseFilename).

Fix

One line on dev: getattr fallback so handlers without baseFilename yield None instead of crash. Dev already guarded empty handlers list but not missing attribute; this strengthens it. Normal FileHandler path unchanged (real path preserved).

Before: logger.root.handlers[0].baseFilename if handlers else None -> AttributeError under pytest
After: getattr(handlers[0], 'baseFilename', None) if handlers else None -> None under pytest, real path normally

Tests

• Repro instantiating BusKill under pytest: FAILED before (exact AttributeError), passes after (LOG_FILE_PATH None)
• Edge: no handlers None, NullHandler None, StreamHandler None, FileHandler real path, mixed None no crash (5/5)
• py_compile clean (pre-existing SyntaxWarnings only)
• Note: LOG_FILE_PATH None only in test/embedded contexts; main.py always configures FileHandler so app unaffected. macOS root-child argv consumer noted.

Files

• src/packages/buskill/init.py (1 line)