[WIP] feat: add Mathlib.Biology.Longevity.PhenoAge formal contract (K-Lean Phase B)

[Heime-Jorgen]

Summary

Add Mathlib.Biology.Longevity namespace with formal Lean 4 contracts for biological age algorithms.

Motivation

The Kenosian Protocol Platform (KPP) provides machine-verifiable audits for bioinformatics algorithm computations. K-Lean Phase A (live) verifies JSON Schema I/O contracts via REST API. Phase B (this PR) provides Lean 4 formal theorems so any researcher can verify locally without trusting a server.

What this adds

• Mathlib/Biology/Longevity/Basic.lean — common types (ValidAge, ageAcceleration)
• Mathlib/Biology/Longevity/PhenoAge.lean — formal contract for PhenoAge (Levine et al. 2018, Aging)

Theorems

• mortalityScore_pos: M > 0 for any linear score xb
• mortalityScore_lt_one: M < 1 for any xb
• phenoAge_wellDefined: PhenoAge is a well-defined real number for any xb

Reference

Levine ME et al. "An epigenetic biomarker of aging." Aging 2018;10(4):573–591.
PLOS Medicine correction 2019 (divisor 0.090165).

K-Lean integration

require KLean from git
  "https://github.com/Heime-Jorgen/kenosian-lean4" @ "main"

Phase A API: POST https://kpp.kenosian.com/api/v1/verify/klean
Contact: peter@kenosian.com

---

This is a draft PR. Proof completeness and Mathlib style compliance are work in progress.

[github-actions]

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[github-actions]

PR summary 7a11bff36f

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
Mathlib.Biology.Longevity.Basic (new file)	1752
Mathlib.Biology.Longevity.PhenoAge (new file)	1753

---

Declarations diff (regex)

+ B
+ ValidAge
+ ageAcceleration
+ exp_γ_τ_pos
+ mortalityScore
+ mortalityScore_lt_one
+ mortalityScore_pos
+ phenoAge
+ phenoAge_wellDefined
+ γ
+ γ_pos
+ τ
+ τ_pos

You can run this locally as follows

## from your `mathlib4` directory:
git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci

## summary with just the declaration names:
../mathlib-ci/scripts/pr_summary/declarations_diff.sh <optional_commit>

## more verbose report:
../mathlib-ci/scripts/pr_summary/declarations_diff.sh long <optional_commit>

The doc-module for scripts/pr_summary/declarations_diff.sh in the mathlib-ci repository contains some details about this script.

Declarations diff (Lean -- pending)

Computed after the build finishes.

---

No changes to strong technical debt.

No changes to weak technical debt.

Current commit 7a11bff36f
Reference commit 6923f2f175

This script lives in the mathlib-ci repository. To run it locally, from your mathlib4 directory:

git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci
../mathlib-ci/scripts/reporting/technical-debt-metrics.sh pr_summary

• The relative value is the weighted sum of the differences with weight given by the inverse of the current value of the statistic.
• The absolute value is the relative value divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).