fix(storage): Close meter provider after client close

[krishnamd-jkp]

No description provided.

[gemini-code-assist]

Code Review

This pull request introduces two positive changes: it corrects the shutdown order of the gRPC connection and the metrics provider to prevent lost metrics, and it avoids shutting down a user-provided meter provider, which is proper resource lifecycle management. My review focuses on a latent bug in the metrics shutdown logic where an expired context is used, which would cause shutdown to fail. I've also pointed out that shutdown errors are not being handled. I've provided suggestions to fix these issues by using a new context for the shutdown operation and propagating any errors to the caller.

[gemini-code-assist]

The close function should return an error to propagate the result of provider.Shutdown. The Shutdown method on MeterProvider can return an error (e.g., if the shutdown context times out) which should be handled by the client's Close method.

Suggested change

	close func()
	close func() error

[gemini-code-assist]

There are two issues with the current implementation of close:

1. The function captures ctx from newGRPCMetricContext. This context is associated with client initialization and is likely to be expired when client.Close() is called. This would cause provider.Shutdown(ctx) to fail. A new context should be created for the shutdown process.
2. The error returned by provider.Shutdown is ignored. This error should be returned to the caller.

Note that after this change, grpcStorageClient.Close() will also need to be updated to handle the error returned from metricsContext.close().

		close: func() error {
			if isDefault {
				// Use a background context with a timeout for shutdown to ensure
				// it can complete even if the original context is expired.
				shutdownCtx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
				defer cancel()
				return provider.Shutdown(shutdownCtx)
			}
			return nil
		},