Create initial contents for new onnxruntime-swift-package-manager repo

[YUNQIUGUO]

Create initial contents for new onnxruntime-swift-package-manager repo

• Create and pull initial objective-c header files and SPM support from ORT main repo : rel-1.15.0 branch.
  • Package.swift file is in sync with rel-1.15.0version
• Set up initial azure CI test pipelines
• Initial README.md
• Test swift project: https://github.com/YUNQIUGUO/ORT-SPM-Test-App
  • Created a simple swift app via Xcode and tried to add Package dependency from this new repo and consumes OnnxruntimeBindings target in the test app. Looks to work.
  • More screenshots in the test repo about how swift user will add this new repo in their project.

Need to see how we want to sync the ORT main objc/swift files later and the release process

• See how to set up jenkins or github actions, etc. to monitor changes from objc files in ORT main repo and automatically syncing the changes to this separate repo.
• Or manually pull changes from main ORT repo in a period of time/before release.

[YUNQIUGUO]

TODO:

• sync all the header files from rel-1.15.0 branch
• run CI tests for Package.swift in two configurations
  • 1. Set ENV and testing the latest (upcoming)
  • 2. Test latest release version (doesn't break the current)

[YUNQIUGUO]

thanks for all the valuable comments! will try to address them all.

[YUNQIUGUO]

The first pull request is not configured as "squash and commit"

I just elevated my repo manage access and changed the settings for pull requests here. Hopefully starting from the next one, it will all be squashed and then check-in as one commit matching the pr title description.