starknet_os: move blake constants to struct scope

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• starknet_os: recompute and assert the blake constants #14032 : 2 dependent PRs (#14033 , #14035 )
• blockifier: fix blake estimation offset by fixing constants #14034
• starknet_os: move blake constants to struct scope #14031 👈 (View in Graphite)
• starknet_os: extract cairo blake run to function #14030
• main

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PR Summary

Low Risk
Low risk refactor that only changes how Blake hash estimation constants are defined/visible; behavior should remain the same, but any downstream code relying on the previous private visibility could be affected.

Overview
Moves the empirical Blake hash estimation constants used by CasmV2HashResourceEstimate from function-local consts to public associated constants on the struct, and updates the estimator to reference them via Self::….

This makes the constants reusable outside the function while keeping the step-calculation logic unchanged (including base costs for full vs partial 16-u32 messages and per-felt step multipliers).

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