BMCT-SLZ: fix z2m crash if device is not reachable on startup

[slugzero]

I noticed that in some cases z2m crashes right after startup, which is caused by an uncaught exception when there is no route to the device. So we better catch everything.

[Koenkk]

This shouldn't be necessary, can you provide the debug log of the crash?

See this on how to enable debug logging.

[slugzero]

I agree, this should not be necessary. For other errors (UNSUPPORTED_ATTRIBUTE, MAC no ACK) the error was caught properly. If you'd like to dive deeper into this, I shared the full log privately: https://github.com/slugzero/z2m-logs/blob/main/z2m-20240102.log

However, for that particular device, I'd like to add these additional catch statements anyway: They also suppress some unnecessary error messages during configuring. Since the device must be configured to behave either as roller shutter or switch, one of the read commands always returns UNSUPPORTED_ATTRIBUTE.

[Koenkk]

I see, then this can be merged indeed!