[Local Catalog] Add remote ID for attributes

[joshheald]

Part of: WOOMOB-1339

Description

This PR updates our attribute schemas to support both Global and Local attributes.

Global attributes are defined independently, and can be reused across products/variations with a many to many relationship. Local attributes are defined per-product or variation, and have a one to many relationship.

We model this with two different tables, but it would make it more difficult to deal with the attributes as we'd need two relationships from the product/variation to its attributes.

Instead, I've opted to mirror the API approach. id remains, as an auto-generated integer, but now the attribute tables include a remoteAttributeID. Global attributes have a positive integer ID, while local attributes have the ID 0.

This approach means the data is denormalised.

Steps to reproduce

This can't be properly tested in the app yet, as the database isn't used in the POS UI.

You can put breakpoints in the POSCatalogPersistenceService.replaceAllCatalogData(_:siteID:) function and check that they are created, or find the SQLite database file from your simulator and open it with a tool like SQLPro... but mostly, just checking that it logs the expected number of products/variations being synced should be enough. We'll see any issues soon enough when it's in the UI, anyway.

You can get the database file for a running simulator by:

1. run xcrun simctl get_app_container booted com.automattic.woocommerce data in the terminal
2. Cmd-G in Finder and paste the path
3. Open Documents
4. You should see woo-local.sqlite

Screenshots

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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.

[wpmobilebot]

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

	App Name	WooCommerce iOS Prototype
	Build Number	pr16219-68f79cd
	Version	23.4
	Bundle ID	com.automattic.alpha.woocommerce
	Commit	68f79cd
	Installation URL	1rp6rt29kqnjg

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

[jaclync]

LGTM! TIL about accessing simulator data with xcrun simctl get_app_container booted com.automattic.woocommerce data. Tested with DataGrip and the remote attribute ID column is set with zero and non-zero values.