fix(dialog): do not create file copy for save file picker on iOS

[nashaofu]

On iOS the file picker returns a security scoped resource file path on the save() file picker: https://developer.apple.com/documentation/uikit/uidocumentpickerviewcontroller?language=objc#Work-with-external-documents

this means we can't directly access it without calling startAccessingSecurityScopedResource

this PR changes the plugin to not access the save file early, leaving that to the user and returning its actual path

fix #2089

[github-actions]

Package Changes Through b4cfd60

There are 6 changes which include http with patch, http-js with patch, deep-link with patch, deep-link-js with patch, fs with patch, fs-js with patch

Planned Package Versions

The following package releases are the planned based on the context of changes in this pull request.

package	current	next
api-example	2.0.23	2.0.24
api-example-js	2.0.19	2.0.20
deep-link-example-js	2.2.0	2.2.1
deep-link	2.2.0	2.2.1
deep-link-js	2.2.0	2.2.1
fs	2.2.0	2.2.1
fs-js	2.2.0	2.2.1
dialog	2.2.0	2.2.1
dialog-js	2.2.0	2.2.1
http	2.4.2	2.4.3
http-js	2.4.2	2.4.3
persisted-scope	2.2.0	2.2.1
single-instance	2.2.2	2.2.3

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[lucasfernog]

nice catch. I think we still need some improvements here, for instance now I couldn't access the file without https://developer.apple.com/documentation/foundation/nsurl/1417051-startaccessingsecurityscopedreso?language=objc

I think we should add that to the FS plugin too

[nashaofu]

Add two methods to fs startAccessingScopedResource and stopAccessingScopedResource? Or I hope to automatically add these two methods before and after the fs call