Add Multiprocessing to Forecasts

[mxkpp]

In support of adding multiprocessing capability to the forecast workflow, this adjusts the step of building the forecast realization, to call the partition generator and create a new partition configuration file, placed in the forecast realization folder.

To support this, provide a ParallelConfig instance in the InputConfig instance when using RealizationBuilder.

This was tested in conjunction with the following PRs:

Forcing: NGWPC/ngen-forcing#120

Forecast Manager: NGWPC/nwm-fcst-mgr#10

RTE: NGWPC/nwm-rte#42

[mxkpp]

Rebased

[kyle-larkin]

The partition_config_basename_prefix wasn't set when I tested, so the output file was _partition_config.json (just the suffix).

How is the prefix set? I may have just missed a step.

[mxkpp]

It was intentional on my part to keep the file name generic (no prefix). If more information should be added to the partition config file I can make that change.

[kyle-larkin]

It was intentional on my part to keep the file name generic (no prefix). If more information should be added to the partition config file I can make that change.

I'm ok with no prefix, but that makes it a little strange that there is a partition_config_basename_prefix variable, which the logger uses to produce the following:

2026-03-27T12:29:19.640 MSWM INFO Creating partition file for

I think if the variable exists, then it should be either optional, have a default value, or be set each time.

[mxkpp]

It was intentional on my part to keep the file name generic (no prefix). If more information should be added to the partition config file I can make that change.

I'm ok with no prefix, but that makes it a little strange that there is a partition_config_basename_prefix variable, which the logger uses to produce the following:

2026-03-27T12:29:19.640 MSWM INFO Creating partition file for

I think if the variable exists, then it should be either optional, have a default value, or be set each time.

I pushed a change that results in the partition config files being named generically "forecast_partition_config.json" instead of "_partition_config.json", and the log msg now reads like "Creating partition file for forecast"

[kyle-larkin]

Changes are good.