Remo/bump tools

[remollemo]

This change is 

[cursor]

PR Summary

Medium Risk
Moderate risk because it upgrades core build/test tooling (scarb, starknet-foundry, snforge_std) which can change compilation/testing behavior and CI results, but it doesn’t touch runtime contract logic.

Overview
Bumps Cairo/Starknet tooling versions across local dev and CI: starknet-foundry to 0.60.0 and scarb to 2.18.0 (including publish workflows and .tool-versions).

Updates workspace dependencies/lockfile to match (assert_macros/starknet 2.18.0, snforge_std 0.60.0) and expands Scarb config to allow the prebuilt snforge_scarb_plugin (in workspace and per-package Scarb.toml files).

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