Add initial-algebra induction and categorical Lindstrom characterization#1
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…racterization Point A: InitialAlgebraInduction.lean — named induction/recursion principles for the Adamek fixed point (adamek_induction, adamek_rec, factorization and uniqueness lemmas). Makes explicit that "proofs by dimension" are instances of initial-algebra induction over the M-chain. Point B: ComputationallyUniversal, categorical_lindstrom, and computationally_universal_of_tensor added to ConvergenceCriterion.lean. Makes "computationally universal" a model-theoretic property of a category-with-structure rather than a property of encodings. 43 files, 0 sorry, 0 custom axioms.
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Summary
InitialAlgebraInduction.lean— names the catamorphism as an explicit induction/recursion proof schema (adamek_induction,adamek_rec). "Proofs by dimension" are instances of initial-algebra induction over the M-chain.ComputationallyUniversal,categorical_lindstrom, andcomputationally_universal_of_tensoradded toConvergenceCriterion.lean. Makes "computationally universal" a model-theoretic property of a category-with-structure (Lindstrom-type characterization).43 files, 0 sorry, 0 custom axioms.
lake build FixedPointpasses clean.Test plan
lake build FixedPoint— 3352 jobs, 0 errorslean_diagnostic_messages— 0 errors, 0 warnings on both new/modified files./scripts/verify.sh— 0 sorry, 0 custom axioms (exit 1 is pre-existing long-line warning in MonoidalUniqueness.lean, not from this PR)