[codex] Clean up curated deploy artifacts

[skhomuti]

What changed

• Stop writing the legacy DeployParams alias from the curated deployment script.
• Update curated deployment test helpers to decode .CuratedDeployParams directly.
• Drop the legacy DeployParams key from the committed Hoodi and mainnet curated deployment artifacts.
• Reuse the existing curated dummyImpl placeholder for the ValidatorStrikes proxy instead of deploying a second Dummy implementation.

Why

Curated deployment params use the CuratedDeployParams Solidity type, while DeployParams is already the CSM deployment params schema. Keeping both keys in curated artifacts made the canonical source ambiguous and allowed tests to keep depending on the legacy alias.

The curated script also deployed Dummy twice even though the first placeholder implementation can be reused for the later ValidatorStrikes proxy.

Validation

• forge build script/curated/DeployBase.s.sol test/helpers/Fixtures.sol

After rebasing onto origin/develop with mainnet CMv2 deployment artifacts, Foundry reported no changed files and skipped recompilation; the same targeted build had passed before the rebase.