Subscribers: Add notice of how many subscribers were added, skipped, failed.

[allilevine]

Related to #97994

Proposed Changes

• Show a more detailed notice when a subscriber import completes. I also looked into showing an error message in the form, but we don't have this data until the import completes. Rather than keep the form open for however long it takes, or ask the user not to navigate away, this notice shows when the data is ready.

Why are these changes being made?

• To show the user how many of their subscribers were imported, already existed, or failed.

Testing Instructions

• Go to /subscribers/{site URL}
• Import a mix of new and existing addresses, and check that the notice reflects the import correctly.
• Test both manual and CSV importing.
• Check that you can dismiss the notice.

Note that if you import with categories, you'll get 0 already subscribed because we re-import with the correct categories.

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 UI changes, have we tested the change in various languages (for example, ES, PT, FR, or DE)? The length of text and words vary significantly between languages.
• 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-aUh-p2)?

[github-actions]

Calypso Live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-130517

Jetpack Cloud live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-130517&env=jetpack

Automattic for Agencies live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-130517&env=a8c-for-agencies

[matticbot]

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

Sections (~501 bytes added 📈 [gzipped])

name         parsed_size           gzip_size
subscribers       +692 B  (+0.1%)     +401 B  (+0.1%)
people            +255 B  (+0.0%)      +71 B  (+0.0%)
import             +95 B  (+0.0%)      +29 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 (~1509 bytes added 📈 [gzipped])

name                                                 parsed_size           gzip_size
async-load-calypso-my-sites-stats-pages-subscribers      +5647 B  (+3.9%)    +1509 B  (+3.0%)

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.

[matticbot]

This PR modifies the release build for the following Calypso Apps:

For info about this notification, see here: PCYsg-OT6-p2

• notifications
• wpcom-block-editor

To test WordPress.com changes, run install-plugin.sh $pluginSlug add/real-time-subscriber-import-results on your sandbox.

[allilevine]

I've added completedJob to return the data we get from the import endpoint response.

[allilevine]

This message shows until dismissed.