workspace,starknet_proof_verifier: bump privacy-{prove,circuit-verify} to 95bc227, add v0 alias

Picks up the keccak builtin simulation in the privacy bootloader
(starkware-libs/proving-utils#342 by @yuvalg) plus the regenerated circuit
verifier constants (starkware-libs/proving-utils#343), allowing virtual-OS
proofs that exercise the keccak builtin to be generated and verified.

The rev points at Yoni-Starkware/proving-utils because the relevant fix
commits are not yet merged upstream; switch to a starkware-libs rev once
proving-utils#343 (and its base PRs #341, #342) land.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: Yoni-Starkware