[Shipping labels] Use backend data for saved packages

[bozidarsevo]

#14506

Description

• Added WooShippingAddPackageViewModel, that model will be used for loading and using packages from the backend response
• In this PR we are using the saved packages and in [Shipping labels] Use backend data for carrier (predefined) packages #14518 we will use the carrier packages

Testing information

• Install and set up the Woo Shipping extension on your store.
• Build and run the app with the revampedShippingLabelCreation feature flag enabled.
• Create an order with the processing status and at least one physical product.
• In the order details, select "Create Shipping Label."
• Store options will start fetching from backend in the background.
• Tap "Select a Package" button
• Switch to "Saved" tab and check that are saved packages in the list, if there are none, be sure to add at least 1 custom package in the "custom" tab in the app or on web

Screenshots

Simulator.Screen.Recording.-.iPhone.16.Pro.-.2024-11-27.at.14.08.34.mp4

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• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

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[wpmobilebot]

📲 You can test the changes from this Pull Request in WooCommerce iOS by scanning the QR code below to install the corresponding build.

	App Name	WooCommerce iOS
	Build Number	pr14517-848163d
	Version	21.2
	Bundle ID	com.automattic.alpha.woocommerce
	Commit	848163d
	App Center Build	WooCommerce - Prototype Builds #11949

Automatticians: You can use our internal self-serve MC tool to give yourself access to App Center if needed.

[dangermattic]

	1 Warning
⚠️	This PR is larger than 300 lines of changes. Please consider splitting it into smaller PRs for easier and faster reviews.

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