Function read_deployment_map 

pub fn read_deployment_map(
    fs: &dyn Fs,
    path: &Path,
) -> Result<Vec<DeploymentMapEntry>>

Read and parse a deployment-map TSV file.

Blank lines and #-prefixed comments are ignored. Rows with the wrong column count are skipped silently — the map is best-effort and a truncated file should not crash the reader.