TypeOverrides

This release introduces TypeScript support for correctly typing the cache instance when using custom cache implementations with Apollo Client.

Apollo Client 4.2 introduces optional "classic" and "modern" method/hook signatures to improve type accuracy based on default options. This release also adds comprehensive support for automatic event-based query refetching via the new RefetchEventManager.

This release makes data‑masking types opt‑in only, removes the `mode` option and the `Masked`/`MaskedDocumentNode` types, and requires migration steps to adjust type declarations.