🧹 Refactor _is_dangerous_rm by extracting _parse_rm_args

[google-labs-jules]

🎯 What: Extracted the argument parsing logic from _is_dangerous_rm into a new helper function _parse_rm_args.
💡 Why: _is_dangerous_rm in hooks/security_guard.py was too long, heavily indenting and combining two responsibilities: iterating sub-commands and tracking states while parsing shell arguments. This improves readability and adherence to the single-responsibility principle.
✅ Verification: Ran python -m pytest tests --cov=hooks --cov-report=term-missing. Tests all passed (264 items) with 99% coverage, proving it's functionally identical.
✨ Result: A more concise and maintainable _is_dangerous_rm function.

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PR created automatically by Jules for task 12705446768601268324 started by @zknpr

[google-labs-jules]

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