S3: go directly to folder/bucket by pasting URL/ARN

Idea from https://www.github.com/aws/aws-toolkit-jetbrains/issues/2547 :

> the ability to just paste an S3 URI and have it load in the AWS Explorer would be great too.

## UI proposal

- Customer can paste an S3 bucket/folder/object URL or ARN to reveal it in the AWS Explorer.
- Add the bucket to the Explorer tree if the bucket isn't shown yet (e.g. because of lack of ListBuckets permission #1807 )
- What about other resources, not only S3? (Lambda functions, CloudWatch log groups/streams, ...)

Start by reviewing the AWS Explorer navigation flow and the linked AWS Toolkit for JetBrains issue. Define which S3 bucket, folder, object URLs and ARNs are supported, how an undisplayed bucket is revealed, and whether other AWS resources are included; done means the agreed inputs navigate to the correct Explorer item.

Written by the indexing model from the issue text.