PLCnext/PLCnext_RT_Datalogger — reverse-engineered prompt

Build me a working PLCnext Control real time datalogger example for firmware 2025.6. I want something I can use to log a few Global Data Space port variables, keep the samples in RAM first, then save them into a database on the controller at a configurable interval, and have the service start and stop with the firmware.

Please include a simple PLCnext Engineer project, the datalogger configuration I need to copy to the device, and clear setup notes for connecting to a PLC on a local IP like 192.168.1.10. I also want the example to show how to expose the logged data through OPC UA historical access, how to read back the datalogger configuration and logged values through the IDataLogger service, and how to send logged data to another device over PROFINET if that is part of the sample.

Keep it practical and easy to follow, with sensible defaults and comments so I can actually run it. Look up current PLCnext docs online if you need to.