[SL-ONLY] Provide prints for hooks for customer on demo application

[Rohan Sahay (rosahay-silabs)]

Summary

As requested by agarwal57 , adding sample of OnPlatform handler and printing the events requested by customer on the demo application.

Related issues

N/A

Testing

Verified the prints on disconnection and reconnection events, the commissioning events are not seen completely as the service starts post WiFi connectivity.

[Rohan Sahay (rosahay-silabs)]

bugbot review

[cursor]

PR Summary

Low Risk
Example-only logging and event registration in the MQTT demo; no production Matter stack or security behavior changes.

Overview
Adds a sample CHIP device-layer event hook to the Silabs thermostat MQTT demo so customers can see how to react to connectivity and commissioning lifecycle events.

On first MQTT client init, the demo now registers OnPlatformEvent via PlatformMgr().AddEventHandler and logs progress messages for WiFi connect/disconnect (kWiFiConnectivityChange), commissioning complete, and secure session established (labeled as commissioning started). Registration failures are logged and cause mqtt_client_demo_start to return failure.

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Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

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Wrong event for commissioning started

Medium Severity

kSecureSessionEstablished is logged as commissioning start, but that event fires for every PASE and CASE session. After commissioning, each controller reconnect prints Commissioning Started, which misleads the customer logs this sample is meant to provide.

 

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