th verify: generalize constructor args encoding beyond 0/2 inputs

[snissn]

Context

• Follow-up from PR Sepolia happy-path: th verify (Etherscan+Sourcify) + chain-config recording #5 (th verify improvements).

Problem

• th verify currently supports encoding constructor args only for arity 0 or 2 (admin + treasury).
• If the generator evolves the App constructor (e.g. adds parameters), verification will break.

Proposal

• Generalize constructor args encoding for verification.
  • Source of truth should be the manifest + compiled ABI.
  • For each constructor input, determine the value from the manifest (or CLI overrides).
  • Fail with a clear error if a required input cannot be resolved.

Options

• Introduce manifest.deployments[].constructorArgs (ordered array) recorded during th deploy.
• Or introduce manifest.deployments[].constructorArgsByName (object) and map into ABI order.
• Or add th verify --constructor-args <hex> override while keeping manifest as default.

Acceptance criteria

• Verification works for any constructor arity where args can be resolved from the manifest (or CLI override).
• Existing 0/2-arg deployments remain backwards compatible.