starknet_api,starknet_proof_verifier: rename PROOF_VERSION to PROOF_VERSION_V0

[Yoni-Starkware]

No description provided.

[cursor]

PR Summary

Low Risk
Low functional risk since the proof version value and validation behavior are unchanged; main risk is a compile-time breaking API rename for any downstream code still importing PROOF_VERSION.

Overview
Renames the proof-facts version marker constant from PROOF_VERSION to PROOF_VERSION_V0 across starknet_api and updates all call sites (test utilities, proof-facts parsing/validation, and the proof verifier).

Test assertions and error messages/docs were adjusted to reference PROOF_VERSION_V0, keeping the proof-facts format and expected marker value ('PROOF0') the same.

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[reviewable-StarkWare]

This change is 

[Yoni-Starkware]

• workspace,starknet_proof_verifier: bump privacy-{prove,circuit-verify} to 69ed219, add legacy alias #14017
• starknet_proof_verifier: add v0.14.3 regression case for PROOF_VERSION_V1 fixture #14016
• starknet_api,starknet_proof_verifier: write PROOF_VERSION_V1 in try_into_proof_facts #14015
• apollo_starknet_os_program,starknet_os: support PROOF_VERSION_V1 in check_proof_facts #14014
• starknet_proof_verifier: accept either PROOF_VERSION_V0 or PROOF_VERSION_V1 in verify_proof #14013
• starknet_api: add PROOF_VERSION_V1 and accept either marker in ProofFactsVariant #14012
• starknet_api,starknet_proof_verifier: rename PROOF_VERSION to PROOF_VERSION_V0 #14011 👈 (View in Graphite)
• main

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• Started at 2026-05-10T14:35:12Z

[AvivYossef-starkware]

@AvivYossef-starkware reviewed 5 files and all commit messages, and made 1 comment.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on Yoni-Starkware).