[Watch App] Adds initial WooWatchApp setup

[Ecarrion]

closes #12641 closes #12645

Why

This PR adds the ⌚ target to the main WooCommerce iOS Project.

How

• Added watch app target as a companion with the iOS App
• Set icons
• Set development provisioning profile
• Set VALID_ARCHS build setting to $(ARCHS_STANDARD), otherwise it will not compile.

Testing Steps

• [x] Make sure the watch app runs via code in the simulator
• [x] Make sure the watch app runs via code in a real device
• [x] Make sure the watch app runs via the installable build?

---

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

[Ecarrion]

Hi @iangmaia, 👋

Following the Watch App provisioning profiles you created. Can you help us set them on our installable builds to test that everything works correctly?

I see on the docs that it is supported, but I don't have the correct role to make any change.

Additionally, if possible, feel free to configure testflight too! 😇

[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	pr12647-b1f955c
	Version	18.4
	Bundle ID	com.automattic.alpha.woocommerce
	Commit	b1f955c4c5172948088b8c3236032ede6fa082ef
	App Center Build	WooCommerce - Prototype Builds #9002

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

[iangmaia]

@Ecarrion I took the freedom to commit directly to this branch, I hope it's ok 😇 . I think it should all be working now, thanks for the ping! 🚀

[Ecarrion]

Thanks a lot @iangmaia, I just had to adjust a minor thing and now everything seems to be working correctly! 🎉