Reader: Add unread count on lists

[mehmoodak]

Closes: https://linear.app/a8c/issue/READ-555

Proposed Changes

• Add unread count to Lists dropdown available on sidebar.
• Migrate related files to TypeScript

Before	After

Why are these changes being made?

Better CX.

Testing Instructions

• Open /reader
• Verify count appearing on lists dropdown (current gated to Automatticians only)

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?
• For UI changes, have you tested the affected components in dark mode?
• Have you tested accessibility for your changes? Ensure the feature remains usable with various user agents (e.g., browsers), interfaces (e.g., keyboard navigation), and assistive technologies (e.g., screen readers) (PCYsg-S3g-p2).
• 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)?

[matticbot]

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https://calypso.live?image=registry.a8c.com/calypso/app:build-189080

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https://calypso.live?image=registry.a8c.com/calypso/app:build-189080&env=jetpack

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https://calypso.live?image=registry.a8c.com/calypso/app:build-189080&env=a8c-for-agencies

Dashboard Live (dotcom) (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-189080&env=dashboard

Dashboard Live (A4A) (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-189080&env=dashboard-a4a

[github-actions]

Looks like one of the E2E tests has failed.

You can fix them following these steps:

1. Check out this branch locally:

   gh pr checkout 112469

2. Start Claude Code in the repo:

   claude

3. Run the /fix-e2e-tests skill, passing this PR number:

   /fix-e2e-tests 112469
   

[github-actions]

Looks like one of the E2E tests has failed.

You can fix them following these steps:

1. Check out this branch locally:

   gh pr checkout 112469

2. Start Claude Code in the repo:

   claude

3. Run the /fix-e2e-tests skill, passing this PR number:

   /fix-e2e-tests 112469
   

[matticbot]

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

App Entrypoints (~155 bytes removed 📉 [gzipped])

Details

name                 parsed_size           gzip_size
entry-subscriptions       -675 B  (-0.0%)     -155 B  (-0.0%)

Common code that is always downloaded and parsed every time the app is loaded, no matter which route is used.

Sections (~454 bytes removed 📉 [gzipped])

Details

name                                parsed_size           gzip_size
jetpack-cloud-partner-portal              -85 B  (-0.0%)      -47 B  (-0.0%)
a8c-for-agencies-woopayments              -85 B  (-0.0%)      -33 B  (-0.0%)
a8c-for-agencies-team                     -85 B  (-0.0%)      -30 B  (-0.0%)
a8c-for-agencies-sites                    -85 B  (-0.0%)      -49 B  (-0.0%)
a8c-for-agencies-settings                 -85 B  (-0.0%)      -42 B  (-0.0%)
a8c-for-agencies-reports                  -85 B  (-0.0%)      -54 B  (-0.0%)
a8c-for-agencies-referrals                -85 B  (-0.0%)      -54 B  (-0.0%)
a8c-for-agencies-purchases                -85 B  (-0.0%)      -33 B  (-0.0%)
a8c-for-agencies-partner-directory        -85 B  (-0.0%)      -37 B  (-0.0%)
a8c-for-agencies-overview                 -85 B  (-0.0%)      -31 B  (-0.0%)
a8c-for-agencies-migrations               -85 B  (-0.0%)      -31 B  (-0.0%)
a8c-for-agencies-marketplace              -85 B  (-0.0%)      -32 B  (-0.0%)
a8c-for-agencies-learn                    -85 B  (-0.0%)      -34 B  (-0.0%)
a8c-for-agencies-landing                  -85 B  (-0.0%)      -32 B  (-0.0%)
a8c-for-agencies-exclusive-offers         -85 B  (-0.0%)      -42 B  (-0.0%)
a8c-for-agencies-client                   -85 B  (-0.0%)      -34 B  (-0.0%)
a8c-for-agencies-amplify                  -85 B  (-0.0%)      -37 B  (-0.0%)
a8c-for-agencies-agency-tier              -85 B  (-0.0%)      -44 B  (-0.0%)
a8c-for-agencies                          -85 B  (-0.0%)      -32 B  (-0.0%)
site-profiler                             -84 B  (-0.0%)       -8 B  (-0.0%)
site-blocks                               -84 B  (-0.0%)      -49 B  (-0.0%)
security                                  -84 B  (-0.0%)      -49 B  (-0.0%)
reader                                    -84 B  (-0.0%)      -48 B  (-0.0%)
privacy                                   -84 B  (-0.0%)      -48 B  (-0.0%)
performance-profiler                      -84 B  (-0.0%)       -8 B  (-0.0%)
patterns                                  -84 B  (-0.0%)      -11 B  (-0.0%)
notification-settings                     -84 B  (-0.0%)      -49 B  (-0.0%)
me                                        -84 B  (-0.0%)      -49 B  (-0.0%)
jetpack-cloud-agency-dashboard            -84 B  (-0.0%)      -45 B  (-0.0%)
developer                                 -84 B  (-0.0%)      -49 B  (-0.0%)
account-close                             -84 B  (-0.0%)      -49 B  (-0.0%)
account                                   -84 B  (-0.0%)      -44 B  (-0.0%)
a8c-for-agencies-express-checkout         -84 B  (-0.0%)      -27 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 (~20 bytes removed 📉 [gzipped])

Details

name                                              parsed_size           gzip_size
async-load-calypso-reader-sidebar                      -217 B  (-0.1%)      +48 B  (+0.1%)
async-load-signup-steps-site-picker                     -84 B  (-0.0%)      -45 B  (-0.1%)
async-load-signup-steps-difm-site-picker                -84 B  (-0.0%)      -45 B  (-0.1%)
async-load-signup-steps-clone-credentials               -84 B  (-0.1%)      -10 B  (-0.0%)
async-load-calypso-components-jetpack-portal-nav        -84 B  (-0.1%)      -17 B  (-0.0%)

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.