feat(verifier-ray): complete verifier

[YaoJGalteland]

Ports the FRI-based polynomial commitment scheme (PCS) verifier from prover-ray into the Zig verifier-ray, and wires it into the top-level verifier.verify as a mandatory, transcript-bound opening layer. The verifier now authenticates committed claims via a real FRI opening instead of trusting proof-supplied values, and the PCS-authenticated entry_claims are the single source the vanishing sub-verifier re-slices — closing the gap where a prover could feed PCS and vanishing different values for the same column.

Key changes

• New PCS verifier (src/pcs/, 8 files): verify, layout, paired_leaf, reconstruct, fold, tree, params, root — DEEP-quotient reconstruction, Merkle input-tree authentication, and FRI fold/query checks, byte-faithful to prover-ray.
• Fiat-Shamir coin binding (src/verifier.zig, src/protocol/root.zig): a single shared eval coin (zeta) is derived from the transcript at zeta_coin_index and used for all openings; Merkle roots are rebound to the round oracle commitments (not read from the proof). Verified end-to-end: prover-committed zeta matches the verifier's transcript-derived zeta byte-for-byte.
• Codegen (codegen/, +1,134 lines): new pcs.go / pcs_zig.go / actions.go compile a protocol's batch shapes, shift schedules, claim maps, and coin routing into the comptime System the Zig verifier consumes.
• Robustness fixes: DoS guard on round-root counts, dynamic per-module size absorption, OOB guards.

Testing

• End-to-end: pcs_realpcs_test.zig runs a genuine prover-ray protocol (arithmetization + pcs.Compile) through the full verifier.verify; plus coexist (vanishing+PCS link), frip (real FRI opening), and endpoint_binding integration tests, each with tamper-rejection cases.
• Test suite leaned to the e2e path: removed granular internal-helper unit tests and cases already subsumed by golden-vector conformance + e2e coverage (82 → 36 tests). Retained prover-ray conformance vectors and the profiling build canary.

[Copilot]

🟡 Human review recommended

It introduces a large, security-critical cryptographic verification stack (FRI/PCS) and rewires verifier trust/binding semantics, which warrants careful human review even with strong new fixtures/tests.

Pull request overview

Ports and integrates a FRI-based PCS verifier into verifier-ray, making PCS openings transcript-bound and making PCS-authenticated entry_claims the single source of truth for downstream query sub-verifiers (notably vanishing), with new codegen + fixtures to validate end-to-end parity against prover-ray.

Changes:

• Adds a full allocation-free FRI/PCS verifier under verifier-ray/src/pcs/ and wires it into verifier-ray/src/verifier.zig so PCS runs first and routes authenticated claims into vanishing.
• Refactors protocol replay to be transcript-continuing (replayWithTranscript) and binds dynamic module sizes into Fiat–Shamir via a codegen-emitted absorb schedule.
• Introduces Go-based fixture generators + new Zig integration tests (FRI opening cross-check, coexistence, real-protocol PCS, endpoint-cell binding), plus supporting codegen enhancements.

File summaries

File	Description
verifier-ray/testdata/generated/realpcs.zig	New generated “real protocol” PCS+vanishing fixture used for end-to-end verifier tests.
verifier-ray/testdata/generated/frip.zig	New generated FRI/PCS opening-proof fixture emitted from prover-ray for byte-level cross-checking.
verifier-ray/testdata/generated/coexist.zig	New generated coexistence fixture proving PCS-authenticated claims feed vanishing.
verifier-ray/testdata/generate/realpcs.go	Generator for the “real protocol” PCS fixture (runs full arithmetization + pcs.Compile).
verifier-ray/testdata/generate/go.sum	Updates generator module sums after generator dependency changes.
verifier-ray/testdata/generate/go.mod	Adds deps/replace directives so generators build against local prover-ray APIs.
verifier-ray/testdata/generate/frip.go	Generator producing a real multi-round FRI/PCS opening proof via prover-ray/fri.
verifier-ray/testdata/generate/frip_emit.go	Serialization logic to emit frip.zig in the shapes verifier-ray consumes.
verifier-ray/test/verifier_test.zig	Removes minimal verifier smoke tests superseded by PCS-backed end-to-end tests.
verifier-ray/test/vanishing_test.zig	Updates replay API usage and adds OOB safety test for cell_value refs.
verifier-ray/test/transcript_test.zig	Removes transcript unit tests (coverage now comes via golden + PCS tests).
verifier-ray/test/pcs_realpcs_test.zig	New end-to-end test: PCS deployed on a real protocol fixture.
verifier-ray/test/pcs_frip_test.zig	New cross-check: verifier-ray PCS verifier accepts/rejects a real prover-ray opening proof.
verifier-ray/test/pcs_endpoint_binding_test.zig	New integration test proving endpoint-cell soundness via transcript + vanishing binding.
verifier-ray/test/pcs_coexist_test.zig	New end-to-end coexistence test proving PCS↔vanishing claim linkage.
verifier-ray/test/logderivativesum_test.zig	Adds OOB safety tests for cell refs via bounds-checked access.
verifier-ray/test/golden_test.zig	Comment update reflecting replay API naming.
verifier-ray/test/field_test.zig	Removes basic field unit tests (coverage now via PCS/FRI arithmetic + higher-level tests).
verifier-ray/test/all.zig	Updates the test suite entrypoint to include new PCS tests.
verifier-ray/src/verifier.zig	Wires PCS as mandatory, transcript-continuing phase; routes PCS-authenticated claims into vanishing.
verifier-ray/src/query/vanishing.zig	Uses bounds-checked ctx.cell(...) for cell_value and surfaces OOB as a clean error.
verifier-ray/src/query/logderivativesum.zig	Uses bounds-checked ctx.cell(...) and extends error set accordingly.
verifier-ray/src/protocol/root.zig	Adds transcript-continuing replay, dynamic-size absorption schedule, and bounds-checked cell accessor.
verifier-ray/src/pcs/tree.zig	New Merkle branch verification for running-layer trees.
verifier-ray/src/pcs/root.zig	New PCS barrel re-export module for public API convenience.
verifier-ray/src/pcs/reconstruct.zig	New DEEP-quotient reconstruction logic at query points.
verifier-ray/src/pcs/params.zig	New FRI parameter validation + domain-point arithmetic (bit-reversed addressing).
verifier-ray/src/pcs/paired_leaf.zig	New multi-size paired-leaf Merkle opening verification and hashing contract.
verifier-ray/src/pcs/layout.zig	New canonical layout builder from shapes/shifts, including shift validation rules.
verifier-ray/src/pcs/fold.zig	New fold-recurrence checker and octuplet decoding for FRI verification.
verifier-ray/src/pcs/verify.zig	New top-level PCS verification orchestration + transcript-derived challenges.
verifier-ray/src/lib.zig	Exposes PCS modules through the library’s public API surface.
verifier-ray/src/field/koalabear_ext.zig	Adds Ext.halve() support required by the FRI fold recurrence.
verifier-ray/src/crypto/fiat_shamir.zig	Adds transcript snapshot/restore + integer sampling used by PCS challenge derivation.
verifier-ray/docs/fri-pcs-plan.md	New design/implementation plan documenting constraints and module map.
verifier-ray/docs/fri-pcs-link-pr-split.md	New PR-splitting plan documenting how to slice the change safely.
verifier-ray/docs/binding-analysis.md	New binding/soundness analysis documenting trust anchors and enforced bindings.
verifier-ray/codegen/vanishing.go	Aligns dynamic-module indexing with FS absorb schedule; adds generation-time guardrails.
verifier-ray/codegen/system.go	Adds PCS system emission and combined verifier.Systems literal generation.
verifier-ray/codegen/spec_zig.go	Emits dynamic size absorb schedule into protocol.Spec.
verifier-ray/codegen/spec_zig_test.go	Tests for dynamic-size schedule emission in generated Spec.
verifier-ray/codegen/pcs.go	New PCS system extraction from compiled+proven prover-ray protocols (shapes/shifts/maps/roots).
verifier-ray/codegen/pcs_zig.go	New Zig emitter for pcs.verify.System literals (params/shapes/shifts/maps/root provenance).
verifier-ray/codegen/pcs_test.go	New tests validating PCS extraction and Zig emission invariants.
verifier-ray/codegen/go.mod	Builds codegen against local prover-ray APIs via replace directive.
verifier-ray/codegen/coin_routing.go	Emits FS dynamic-size absorb schedule and shared dynamic-module rank mapping.
verifier-ray/codegen/actions.go	New fail-closed guard ensuring all verifier actions are handled/emitted.
verifier-ray/codegen/actions_test.go	Tests that unhandled verifier actions (e.g., grandproduct) are rejected at codegen time.
verifier-ray/build.zig	Adds Zig build modules for new generated fixtures used by the new tests.
prover-ray/wiop/compilers/pcs/pcs.go	Exposes PCS compiler internals needed by verifier-ray codegen/fixtures (CommittedBatches, GetLayout, etc.).
.gitignore	Ignores generator build artifact under verifier-ray/testdata/generate/.

Review details

• Files reviewed: 48/55 changed files
• Comments generated: 1
• Review effort level: Lite

We're testing this review assessment. Please use 👍 or 👎 to tell us if it's correct.