Add retry logic to S3 metadata

[f0reachARR]

…f S3 head object results.

[gemini-code-assist]

Code Review

This pull request enhances the getObjectMetadata function in the storage service by implementing a retry mechanism to handle S3's eventual consistency and transient 404 errors. The changes include new utility functions for metadata validation and error handling, supported by updated unit tests. A review comment suggests adopting an exponential backoff strategy for the retry delay to optimize performance and resource usage.

[gemini-code-assist]

Using a fixed retry delay can be inefficient or lead to unnecessary load during transient failures. Implementing an exponential backoff strategy is generally a best practice for retries, especially when dealing with eventual consistency in cloud services like S3.

Suggested change

	await wait(retryDelayMs);
	await wait(retryDelayMs * Math.pow(2, attempt - 1));