pub fn extract_feature_namespace(paths: &[&str]) -> Option<FeatureNamespace>Expand description
Extract a dominant feature namespace from a set of changed file paths.
Returns Some if a non-generic, non-structural token of sufficient length
appears in ≥ 35% of files across ≥ 2 directory subtrees, with ≥ 4 total files.
After finding a namespace, runs one absorption round to pull in files that share
any qualifying token with existing members.