Critical fixes:
- Add [:safe] option to binary_to_term to prevent RCE attacks
- Implement whitelist validation for String.to_atom conversions
- Add input validation before String.to_existing_atom usage
Changes:
- MIB compiler and cache: Use safe binary deserialization
- SNMP contexts: Whitelist protocol, device type, and source atoms
- API controllers: Validate error message keys before atom conversion
- Reduce function nesting to comply with Credo standards
All 6,145 tests passing with zero Credo issues.
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
