[Woo POS] Extract CartViewModel and TotalsViewModel

[iamgabrielma]

Closes: #

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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.

[dangermattic]

	2 Warnings
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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	pr13179-a28f8e6
	Version	19.2
	Bundle ID	com.automattic.alpha.woocommerce
	Commit	a28f8e6
	App Center Build	WooCommerce - Prototype Builds #9769

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[iamgabrielma]

The reference to the dashboard is currently necessary due to .submitCart(). This calls for syncOrder(for cartProducts: [CartItem]) async which contains OrderService and card reader logic

[iamgabrielma]

This .disabled state relies on the payment state, possibly shouldn't be attached to the cart logic, but totals.

[soundsokay]

Are you planning to move forward with this PR @iamgabrielma?

I noticed it involves isAddMoreDisabled which I've updated in my PR to also take into account order syncing state.

[iamgabrielma]

Thanks for the ping! This can be closed as was just a preliminary draft for the following changes:

• [Woo POS] Extract item selection logic to ItemSelectorViewModel #13188
• [Woo POS] Extract cart logic to CartViewModel #13191
• [Woo POS] Extract totals logic to TotalsViewModel #13211