Bind ZAP1 verifier roots to leaf count and add equivalence corpus

[Zk-nd3r]

This stack completes the count-bound verifier cleanup and makes the verification boundary mechanically checkable across Python, Rust, and TypeScript-family code.

What changed

• Bind ZAP1 Merkle roots to leaf count and gate legacy raw-root verification.
• Update proof bundles, verifier CLIs/SDK/widget, and conformance vectors.
• Add a frozen cross-implementation equivalence corpus and CI workflow.
• Align live API tooling defaults and probe request identity.
• Soften docs/copy around verifiable vs anchored roots.

Why

The previous raw-root verifier surface could not distinguish some legacy odd-leaf tree shapes and left room for server/verifier drift. This PR makes the count-bound verifier path the default, preserves explicit historical legacy compatibility, and adds CI coverage so Python, Rust, and TypeScript-family verifier implementations stay aligned.

Validation

• git diff --check HEAD~4..HEAD
• Python syntax checks for verifier/conformance scripts
• node --check equivalence\typescript\fingerprint.mjs
• Python/Rust/TypeScript equivalence fingerprints match equivalence/fingerprints.expected.txt
• python conformance\zip1243_conformance.py -> 82/82 passed, 0 failed, 2 skipped
• python verify_proof.py --proof examples\proof_bundle_example.json
• python examples\verify_proof.py examples\proof_bundle_example.json
• pytest -q scripts\check_anchor_liveness_test.py -> 4 passed
• cargo test --manifest-path zap1-verify/Cargo.toml --offline -> 24 passed
• cargo test --manifest-path zcash-memo-decode/Cargo.toml --offline -> 23 passed
• python conformance\check_api.py https://api.frontiercompute.cash -> 26 pass, 0 fail
• python examples\conformance_check.py https://api.frontiercompute.cash -> 19 pass, 0 fail

Notes

Strict anchor liveness remains operationally red because anchoring is paused: current state observed locally was needs_anchor=true, unanchored_leaves=1, last anchor age about 1282h. Relaxed monitor mode still reports this as a warning. This PR does not broadcast anchors, restore seed material, or mutate production service state.