SE Theory: Persistence

Lean 4 formalization of foundational persistence theory for Structural Explainability.

The theory classifies transformations as applicable-and-preserving, applicable-and-breaking, applicable-and-ignoring, or inapplicable, and defines what the classification induces on a carrier: directed survival, the identity relation, breakage, and invariants.

Transformation vocabulary belongs upstream. Identity regimes and framework admissibility belong downstream.