Add Config Flag to Explicitly Control Input Field Truncation

[sahahner]

Is your feature request related to a problem? Please describe.

Currently, truncation of input fields is automatically enabled when a path to the truncation matrices is provided. While this implicit control may be convenient in some cases, it reduces clarity and flexibility, especially for users who might provide all hardware configurations in configuration files in their home or want more explicit control over input processing.

Describe the solution you'd like

Introduce a dedicated flag in a configuration file (e.g., apply_truncation: true/false) to explicitly control whether truncation of input fields is applied.

This would decouple truncation behaviour from the presence of a truncation matrix path, making the configuration more predictable and aligned with how other features are toggled.

This change would improve transparency and user control in the configuration.

Describe alternatives you've considered

No response

Additional context

No response

Organisation

ECMWF