lean/Spa.lean

import Spa.Lattice
import Spa.Fixedpoint
import Spa.Isomorphism
import Spa.Lattice.Unit
import Spa.Lattice.Prod
import Spa.Lattice.AboveBelow
Lean migration: Phases 0-2 (core lattice/chain, fixpoint, transport) - lean/ lake project pinned to Lean v4.17.0 + mathlib v4.17.0 - Spa.Lattice: fold monotonicity, FixedHeight/BoundedChains (LTSeries-based), FiniteHeightLattice, chain-bottom-is-least; the rest of Lattice.agda, Chain.agda and Equivalence.agda lift into mathlib (see LEAN_MIGRATION.md) - Spa.Fixedpoint: gas-based least-fixpoint computation (doStep/fix/aFix) - Spa.Isomorphism: FixedHeight transport along monotone inverse pairs Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> 2026-06-09 18:36:43 -07:00			`import Spa.Lattice`
			`import Spa.Fixedpoint`
			`import Spa.Isomorphism`
Lean migration: Phase 3 (Unit, Prod, AboveBelow lattices) - Spa.Lattice.Unit: PUnit fixed height 0 (lattice lifted from mathlib) - Spa.Lattice.Prod: chain unzip + FixedHeight (h1+h2) on products (componentwise lattice lifted from mathlib's Prod.instLattice) - Spa.Lattice.AboveBelow: flat lattice via Lattice.mk' (mirrors the Agda semilattices+absorption construction), boundedness via rank into Nat, Plain x ↦ plainFixedHeight x, height 2 Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> 2026-06-09 18:48:02 -07:00			`import Spa.Lattice.Unit`
			`import Spa.Lattice.Prod`
			`import Spa.Lattice.AboveBelow`