starknet_transaction_prover: add committer utils unit tests

[avi-starkware]

Covers state_maps_to_committer_state_diff (empty / nonces / storage /
compiled class hashes) and validate_virtual_os_state_diff (valid storage,
valid nonce, and rejection of storage deletion / contract deployment /
contract declaration).

[reviewable-StarkWare]

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[avi-starkware]

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• starknet_transaction_prover: add deployment smoke script and guide #14052
• starknet_transaction_prover: add manual testing guide #14404
• starknet_transaction_prover: make RPC error spec test exhaustive via enum #14051
• starknet_transaction_prover: add TLS integration tests #14050
• starknet_transaction_prover: add ServiceConfig validation tests #14049
• starknet_transaction_prover: add CORS validation unit tests #14048
• starknet_transaction_prover: add prover input validation unit tests #14047
• starknet_transaction_prover: add committer utils unit tests #14046 👈 (View in Graphite)
• starknet_transaction_prover: add request body size limit tests #14403
• main-v0.14.3

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PR Summary

Low Risk
Test-only changes with no production logic modifications.

Overview
Adds committer_utils_test and wires it in running.rs so the existing committer helpers are covered by unit tests.

validate_virtual_os_state_diff is exercised with rstest: empty diffs, non-zero storage, and nonce updates should pass; zero storage (deletion), address_to_class_hash (deployments), and class_hash_to_compiled_class_hash (declarations) should fail with ProofProviderError::InvalidStateDiff messages matching expected substrings.

state_maps_to_committer_state_diff is tested for an empty StateMaps, and for preserving nonces, per-contract storage keys/values, and compiled class hash mapping into the committer StateDiff shape.

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• Started at 2026-05-31T10:39:09Z