Data Stores: Refactor WpcomPlansUI store to createReduxStore()

[tyxla]

Proposed Changes

This PR migrates the WpcomPlansUI store to use createReduxStore() and register() instead of registerStore().

Part of #74399. A follow-up to #73890.

Testing Instructions

• Verify /home/YOURSITE?domain=true where YOURSITE is a new simple site, still properly displays the domain upsell component, and that still works well:
  • You can still proceed to purchase your domain
  • You can still purchase the domain with a plan
  • You can still choose the Free plan, and purchase the domain separately.
• Verify /plans still looks and works well.
• Verify all checks are green.

Pre-merge Checklist

• Has the general commit checklist been followed? (PCYsg-hS-p2)
• Have you written new tests for your changes?
• Have you tested the feature in Simple (P9HQHe-k8-p2), Atomic (P9HQHe-jW-p2), and self-hosted Jetpack sites (PCYsg-g6b-p2)?
• Have you checked for TypeScript, React or other console errors?
• Have you used memoizing on expensive computations? More info in Memoizing with create-selector and Using memoizing selectors and Our Approach to Data
• Have we added the "[Status] String Freeze" label as soon as any new strings were ready for translation (p4TIVU-5Jq-p2)?
• For changes affecting Jetpack: Have we added the "[Status] Needs Privacy Updates" label if this pull request changes what data or activity we track or use (p4TIVU-ajp-p2)?

[github-actions]

Calypso Live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:commit-a0d46bf7ae6d378bc72fb357ddf3b3808b690fd1

Jetpack Cloud live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:commit-a0d46bf7ae6d378bc72fb357ddf3b3808b690fd1&env=jetpack

[matticbot]

Here is how your PR affects size of JS and CSS bundles shipped to the user's browser:

Sections (~53 bytes removed 📉 [gzipped])

Details

name   parsed_size           gzip_size
plans       -154 B  (-0.0%)      -53 B  (-0.0%)

Sections contain code specific for a given set of routes. Is downloaded and parsed only when a particular route is navigated to.

Async-loaded Components (~30 bytes removed 📉 [gzipped])

Details

name                                                 parsed_size           gzip_size
async-load-calypso-my-sites-plan-features-2023-grid        -99 B  (-0.2%)      -30 B  (-0.2%)

React components that are loaded lazily, when a certain part of UI is displayed for the first time.

Legend

What is parsed and gzip size?

Parsed Size: Uncompressed size of the JS and CSS files. This much code needs to be parsed and stored in memory.
Gzip Size: Compressed size of the JS and CSS files. This much data needs to be downloaded over network.

Generated by performance advisor bot at iscalypsofastyet.com.

[noahtallen]

Tests well for me!

[chriskmnds]

Thanks for making this refactor! So much better to just import and use these stores.