When getting content for a post, ensure we're always getting the most recent version

[dkotter]

What?

When content about a post is needed when an experiment is triggered, ensure we always grab the most recent version.

Why?

There was a bug report around the Title Generation Experiment and how they added some post content that was about one topic and then changed that content to be about a completely different topic. When generating titles, the titles reflected the first content, not the second.

The issue here is we grab the content from the editor at page load so if the content is changed and the page isn't refreshed, we have the old version of the content stored. Instead we should pull the content fresh each time title generation is triggered.

I audited all of our other Experiments and found similar problems with Excerpt Generation and Featured Image Generation (in particular, generating the image prompt). All of those are fixed now. All other Experiments were working correctly.

How?

• Grab the post content from the editor when title generation is triggered instead of when the component is loaded
• Switch to using the useSelect hook to get the post content and excerpt when Excerpt Generation is triggered to ensure we always have the freshest data
• For the context we send to our Image Prompt Generation Ability, switch away from using our get-post-details Ability and instead directly grab the post title and post type. This ensures we always have the most up-to-date title instead of the latest version stored in the database

Use of AI Tools

None

Testing Instructions

1. Checkout this PR and run npm i && npm run build
2. Turn on Title Generation, Excerpt Generation and Image Generation
3. Create a new post and add a title and some content
4. Ensure all three of those Experiments work
5. Modify the title and content significantly. Don't save or reload
6. Run all three Experiments again and ensure they still work

[github-actions]

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Co-authored-by: dkotter <dkotter@git.wordpress.org>
Co-authored-by: jeffpaul <jeffpaul@git.wordpress.org>

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 58.09%. Comparing base (7d20bba) to head (a15dd32).
⚠️ Report is 88 commits behind head on develop.

Additional details and impacted files

@@            Coverage Diff             @@
##             develop     #367   +/-   ##
==========================================
  Coverage      58.09%   58.09%           
  Complexity       630      630           
==========================================
  Files             46       46           
  Lines           3193     3193           
==========================================
  Hits            1855     1855           
  Misses          1338     1338           

Flag	Coverage Δ
unit	58.09% <ø> (ø)

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