Function load_industry_map 

pub fn load_industry_map<S: ObjectSource>(
    src: &S,
) -> Result<Option<HashMap<String, String>>, DataError>

Load tracked/universe.csv.gz (or .csv) from src into the symbol → sector map the engine’s industry ops consume. Ok(None) when the snapshot is absent or has no usable rows — the runner then leaves the map empty and industry ops treat every symbol as unmapped.