Make mkstemp disposable #67360

What is the problem this feature will solve?

#66484 added mkstemp and mkstempSync, which return an object with path and handle methods. These require manual cleanup:

The file is not removed automatically. It is the caller's responsibility to close the {FileHandle} and to remove the file when it is no longer needed.

What is the feature you are proposing to solve the problem?

That object should have a Symbol.dispose method which removes the file when invoked.

As the PR says:

a disposable variant in the style of fs.mkdtempDisposableSync(). I would leave it for a follow-up, to keep this PR to the plain API.

But mkdtempDisposableSync needed to be a separate API, because it mkdtempDisposable returns a bare string. Here it's returning an object and so could be disposable directly, no need for a new API.

What alternatives have you considered?

No response