fix(storage): Fixing watchOS crash when dealing with big files

[ruisebas]

Issue #

• Runtime Error on Large File Upload - Double to Int Conversion Issue #3378

Description

This PR changes Int to UInt64 in several Storage objects when representing bytes.
watchOS's Int is actually a Int32 due to its arm64_32 architecture, so attempting to convert >= 2GB into bytes results in an overflown error.

The only special handing is our usage of FileHandle.read(upToCount:), which we use to split a file into parts for multipart uploads.
Since the count attribute is an Int, but the theoretical maximum size for a part is 5GB, attempting to directly cast it could crash. In practice, this very unlikely to happen as having a part with size >= 2GB with the current implementation can only happen for files of size bigger than 20TB.

We can argue that by the time an Apple Watch can handle 20TB files, then the arm64_32 architecture would likely be long gone. But anyways, just to be extra cautious, I've prevented this situation by implementing a simple check that will "split" reads that exceed Int.max bytes.

General Checklist

• Added new tests to cover change, if needed
• Build succeeds with all target using Swift Package Manager
• All unit tests pass
• All integration tests pass
• Security oriented best practices and standards are followed (e.g. using input sanitization, principle of least privilege, etc)
• Documentation update for the change if required
• PR title conforms to conventional commit style
• New or updated tests include Given When Then inline code documentation and are named accordingly testThing_condition_expectation()
• If breaking change, documentation/changelog update with migration instructions

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.