Publish claim-by-claim theorem audit and evaluator-visible evidence

Update logbook: Padded Transformer Expressivity: Proof-Instance Audit

Update logbook: Padded Transformer Expressivity: Proof-Instance Audit

Add Lean-kernel formal verification for Theorem 4.2

Replace finite inclusion graph with source-pinned universal proof audit

Update logbook: Reproduction: Revisiting Padded Transformer Expressivity: Which Architectural Choices Matter and Which Don't

Update logbook: Padded Transformer Expressivity: Proof-Instance Audit