Replace algebraic integers with Lean-GAP exercise DF_10_2_1 from the supplied Formal.tar. Preserve its original formal statement byte for byte and package it with the shared Harbor submission, environment and separate Comparator verifier. Keep absolute profinite rigidity as the research task. Update generation, bundled source inventories, initialization and image task-count checks for the mixed sample. Add qualitative difficulty levels and the RL-environment/expert-authored-data messaging; record local validation without shipping test proofs.
