Swim4LIFE™ Multi-Functional End-to-End Beach-Goer Safety System Providing Non-Stop Twenty-Four-Hour Autonomous Aerial Surveillance, Polarised Sub-Surface Optical Hazard Classification at Three-to-Four-Metre Depth, On-Device Privacy-Preserved Multi-Hazard Inference, Engineered Triple-Path No-Blackout Telecommunications Relay, Accessibility-Compliant Multilingual Alerting Including Vibration-Mode Alerting for Deaf-and-Hard-of-Hearing Beach-Goers, and Software-Enforced Operator Authority Tiering Aligned to Surf-Lifesaving Credentials, with Identity-Preserving De-Identified Footage Pipeline.