fix(domains): correct mutation response types - #317

What

Correct the return types of Domains.update, Domains.verify, and Domains.remove, including their async variants.

Why

The SDK types these responses as a full Domain. A caller can read Domains.verify(id)["status"] without a type error, but the API response has no status and the lookup can raise KeyError.

How

• Match the documented update, verify, and delete response shapes. Update the examples to use those types.
• This follows fix: wrong return types for creation methods #159's correction to the domain creation response type.

Testing

• Sync and async tests use the documented response shapes and assert the inferred types.
• tox -e lint,mypy,py passed (862 tests).

Notes for reviewers

This narrows the public type annotations. The request and response data are unchanged. Use Domains.get() to read the current status.

Summary by cubic

Corrects the return types of Domains.update, Domains.verify, and Domains.remove (sync and async) to match the documented API response shapes. Previously these were typed as a full Domain, so callers could read fields like status that aren't in the response and hit a KeyError.

• Adds UpdateDomainResponse, VerifyDomainResponse, and RemoveDomainResponse types with only the fields the API actually returns.
• Updates tests and examples to use the new types and assert them via assert_type.
• Use Domains.get() to read a domain's current status; the request and response payloads are unchanged.

^{Written for commit 82886c4. Summary will update on new commits.}