Function load_computed_layout 

pub fn load_computed_layout<ElementsOutput: Clone + DeserializeOwned>(
    file: &Path,
) -> Result<Vec<ElementsOutput>, Box<dyn Error>>

Loads a vector of layout outputs from a JSON file.

Used in stage 3 (render-only) to skip the layout manager and feed precomputed output directly into a render pipe.

Errors

Returns an error if file reading or JSON deserialization fails.