feat: implement parallel operations

[ddelgrosso1]

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Fixes #1868 🦕 Fixes #2051

[ddelgrosso1]

Opening as a draft PR while I add in JSDoc comments so that I can start gathering feedback / initial thoughts.

[ddelgrosso1]

Repointing this at a new branch named transfer-manager. My plan is to release this as a "preview" from that branch. Since this is a new feature, keeping it in sync with main should be relatively headache free until such a point that we deem the feature stable.

[snippet-bot[bot]]

Here is the summary of changes.

You are about to add 3 region tags.

• samples/downloadFileInChunksWithTransferManager.js:32, tag storage_download_many_files_transfer_manager
• samples/downloadManyFilesWithTransferManager.js:28, tag storage_download_many_files_transfer_manager
• samples/uploadManyFilesWithTransferManager.js:28, tag storage_upload_many_files_transfer_manager

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[ddelgrosso1]

Since this is getting large and most feedback has been addressed going to go ahead and merge this into the staging branch. We can re-review before the final merge to main.