Independent CPU repair core

This independently extractable listing implements:

• the source-aligned protected forward equation;

• exact-count ordinary deletion and permanent scarring;

• repair restricted to inactive unscarred positions;

• separately seeded initial-scar placement;

• complete phase snapshots;

• explicit evaluation and training streams;

• pre-update and post-update records.

The listing changes tie selection and can use a changed, clipped-diagnostic certified controller. It does not claim numerical identity with the original experiment. Its mask operations are explicitly layerwise.

Stable sorting implements flattened-index tie breaking PyTorchArgsort. Environment-specific reproducibility must still be recorded PyTorchRandom.