Audit Fixes: Issue (L, M, N, P, R) - Added evaluation bindings to the transcript

[ocdbytes]

Summary

• Fix evaluation binding soundness bug: Public evaluations are now absorbed into the Fiat-Shamir transcript as prover messages before any batching/combination challenges (α, ρ, constraint_rlc) are sampled. The verifier reads them back and checks verify!(read == expected), rejecting any mismatch immediately.
• Add audit soundness regression tests (src/protocols/audit_soundness_tests.rs) covering three classes of evaluation forgery identified in the security audit, with exact exploit constructions that extract challenge values from the transcript.

Root Cause

Evaluations were not bound in the Fiat-Shamir transcript before the challenges that depend on them. A malicious prover could generate an honest proof, replay the transcript to extract α/ρ/constraint_rlc, then forge evaluations that preserve the challenge-weighted sums the verifier checks.

Audit Issues Addressed

Issue	Description	Fix Location	Tests
L	zkWHIR Batch Proofs Accept Alpha-Cancelled Forged Evaluations	Evaluations absorbed into transcript before alpha_coeffs sampling (whir_zk/verifier.rs:133-136)	test_rejects_alpha_cancelling_forgery (whir_zk/mod.rs:807), test_rejects_all_forgery_patterns_n2_f2 (whir_zk/mod.rs:1163)
M	Unbound Step-2 G_j Claims Allow Rho-Adaptive Forged Evaluations	Evaluations absorbed into transcript before rho sampling (whir_zk/verifier.rs:133-136)	test_rejects_g_claim_forgery_via_rho (whir_zk/mod.rs:866)
N	zkWHIR Multi-Form Proofs Accept Form-RLC-Preserving Forged Evaluations	Evaluations absorbed into transcript before constraint_rlc_coeffs sampling (whir_zk/verifier.rs:133-136)	test_rejects_constraint_rlc_cancelling_forgery (whir_zk/mod.rs:1101), test_rejects_all_forgery_patterns_n2_f2 (whir_zk/mod.rs:1163)
P	WHIR Batched Verifier Accepts Vector-RLC-Cancelled Forged Evaluations	Evaluations absorbed into transcript before vector_rlc_coeffs sampling (whir/verifier.rs:85-88)	test_rejects_forged_eval_separate_commits (whir/mod.rs:1061), test_rejects_forged_eval_batched_commit (whir/mod.rs:1101), test_rejects_alpha_cancelling_forgery (whir/mod.rs:1143)
R	WHIR Multi-Form Proofs Accept Form-RLC-Preserving Forged Evaluations	Evaluations absorbed into transcript before constraint_rlc_coeffs sampling (whir/verifier.rs:85-88)	test_rejects_constraint_rlc_cancelling_forgery (whir/mod.rs:1190)