starknet_api,starknet_proof_verifier: write PROOF_VERSION_V1 in try_into_proof_facts

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PR Summary

Medium Risk
Changes the proof-facts version marker from V0 to V1 when converting bootloader output, which can break consumers that still assume V0 and could affect proof verification interoperability.

Overview
Updates ProgramOutput::try_into_proof_facts to write ProofVersion::V1 (instead of V0) as the leading marker in generated ProofFacts, aligning newly produced proof facts with the current proof version.

Adjusts documentation/comments and the roundtrip unit test to expect V1, and loosens reconstruct_output_preimage wording to treat the first element generically as PROOF_VERSION_V*.

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• 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 👈 (View in Graphite)
• 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
• main

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• Started at 2026-05-10T15:07:20Z

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