analyze.sx projects DAG edges to (edge in out) facts and runs recursive
reachable rules for deps-of/dependents-of/reachable-from/ancestors-of, plus
dirty-closure (dirty(Y):-edge(X,Y),dirty(X)) for incremental recompute. Keystone:
changing a mid node dirties only it + downstream. analyze 16/16, total 36/36.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
