[Integration] Integration between Backend, IOT, Frontend

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The issue title mentions integration between backend, IoT, and frontend, but the body is empty. No specific files, tests, or entry points are indicated. A newcomer would need to understand the overall architecture, communication protocols, and data flows between these systems. Start by examining the repository structure to identify existing backend, IoT device, and frontend components, then determine how they currently interact and what integration gaps exist.

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