Upgrade @metamask/preferences-controller to version 19.0.0

A new major version of `@metamask/preferences-controller`, 19.0.0, is now available. This issue has been assigned to you and your team because you code-own this package in the `core` repo. If this package is present in this project, please prioritize upgrading it soon to unblock new features and bugfixes.

Start by searching the repository's package manifests and lockfiles for @metamask/preferences-controller, then inspect how the current version is used before attempting the major upgrade. Done means the dependency resolves to 19.0.0, the lockfile is updated consistently, and the repository's existing checks pass; no specific file or test is named in the issue.

Written by the indexing model from the issue text.