BACnet support

### Use Case

I think it would be great to have BACnet support, as it is often used for BMS systems (where it was convenient to use it in conjunction with InfluxDB).

### Expected behavior

Telegram must in its configuration connect to the BACnet object by BACnet ID, IP address and controller port and read all attributes (variables) of the BACnet object.

### Actual behavior

Not provided

### Additional info

_No response_

No files, tests, or entry points are named. First clarify the BACnet library and protocol scope, then review Telegraf's existing input integrations; done would mean a defined configuration that connects using the BACnet ID, IP address, and controller port and reads the requested object attributes.

Written by the indexing model from the issue text.