[Tags Feed] Implement pull-to-refresh

[thomashorta]

Fixes #20707

Add pull-to-refresh to Tags Feed, which reloads the user's sites and tags then "restarts" the Tags Feed, fetching newer posts for each of the tags.

This also fixes the wrong post image being shown (it was showing the site avatar instead of the featured image).

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To Test:

1. Open Jetpack
2. Turn on reader_tags_feed feature config
3. Go to Reader
4. Go to Tags feed
5. Scroll a bit, waiting for the posts to load
6. Wait a few minutes (optional: go to another device/web and follow a new tag)
7. Pull to refresh in the Tags feed
8. Verify the tags are refreshed
9. Verify the posts are loaded for all tags

Note: also verify that the post images are now correct.

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Regression Notes

1. Potential unintended areas of impact

   • N/A

2. What I did to test those areas of impact (or what existing automated tests I relied on)

   • N/A

3. What automated tests I added (or what prevented me from doing so)

   • Updated existing tests
   • Added unit tests for the refresh behavior

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PR Submission Checklist:

• I have completed the Regression Notes.
• I have considered adding accessibility improvements for my changes.
• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

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Testing Checklist (strike-out the not-applying and unnecessary ones):

• WordPress.com sites and self-hosted Jetpack sites.
• Portrait and landscape orientations.
• Light and dark modes.
• Fonts: Larger, smaller and bold text.
• High contrast.
• Talkback.
• Languages with large words or with letters/accents not frequently used in English.
• Right-to-left languages. (Even if translation isn’t complete, formatting should still respect the right-to-left layout)
• Large and small screen sizes. (Tablet and smaller phones)
• Multi-tasking: Split screen and Pop-up view. (Android 10 or higher)

[wpmobilebot]

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

	App Name	Jetpack
	Flavor	Jalapeno
	Build Type	Debug
	Version	pr20791-03d53da
	Commit	03d53da
	Direct Download	jetpack-prototype-build-pr20791-03d53da.apk

Note: Google Login is not supported on these builds.

[wpmobilebot]

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

	App Name	WordPress
	Flavor	Jalapeno
	Build Type	Debug
	Version	pr20791-03d53da
	Commit	03d53da
	Direct Download	wordpress-prototype-build-pr20791-03d53da.apk

Note: Google Login is not supported on these builds.

[develric]

Thanks for the PR @thomashorta 🙇 ! Code is clean and looks good (good job 👍 ).

I tested the PR as per steps and it works correctly. Also checked the posts featured images are now loaded as expected (good catch 👍 ).

I'm approving and we can merge this PR 🎉 .

---

Side note: while testing I noticed something that is not related to this PR (if it's not on the radar already I can create a separate GH issue for later, just let me know 👍 ).

The position in the feed resets to the top of the feed on screen rotation (it seems consistent). This might be annoying when you have many tags you follow and you are deep down the feed and sent to the top. We have more urgent tasks to cover, but as said I'm happy to create a GH issue if needed so we do not forget to improve this along the way 🙇 .

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[codecov]

Codecov Report

Attention: Patch coverage is 76.00000% with 6 lines in your changes are missing coverage. Please review.

Project coverage is 40.79%. Comparing base (4acb2b9) to head (03d53da).

Files	Patch %	Lines
...der/viewmodels/tagsfeed/ReaderTagsFeedViewModel.kt	71.42%	0 Missing and 6 partials ⚠️

Additional details and impacted files

@@                       Coverage Diff                        @@
##           issue/20708-tags-feed-lazy-load   #20791   +/-   ##
================================================================
  Coverage                            40.78%   40.79%           
================================================================
  Files                                 1493     1493           
  Lines                                68627    68642   +15     
  Branches                             11335    11337    +2     
================================================================
+ Hits                                 27991    28003   +12     
- Misses                               38093    38095    +2     
- Partials                              2543     2544    +1     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[develric]

Just leaving a note that I created a GH issue here for the screen rotation issue identified in this comment as per our slack alignment.