feat(google/datastore/v1): onboard a new library

[quirogas]

No description provided.

[gemini-code-assist]

Code Review

This pull request introduces the auto-generated @google-cloud/datastore-api package, onboarding client libraries, protobuf definitions, samples, and tests for both the main Datastore and Datastore Admin APIs. However, a critical issue was identified where sequential generation runs caused the admin API generation to overwrite several shared files. As a result, DatastoreClient is completely missing from the package exports, which breaks the test suite. Additionally, the package description, README links, and webpack configuration are incorrect because they only reference the admin client instead of the entire Datastore API. The generation orchestrator or configuration needs to be updated to ensure both clients are generated and exported together.