WP 7.0: Move away from directly using the AI_Client

[dkotter]

What?

Partially closes #244

Move away from using the AI_Client directly and instead use the new wp_ai_client_prompt function. Also update to use the new Connectors screen instead of the AI Credentials screen. And finally address a few fixes that cropped up now that the OpenAI provider is using the Responses API.

Why?

In the next release, WP 7.0 will be our minimum and as such, we want to rely on the AI Client that is in core instead of bundling that ourselves. This is the final step in a 3-part process to get everything working. Anywhere we were relying on the old approach (AI_Client, AI Credentials screen, built-in providers), as now been updated.

How?

• Update anywhere we were referencing the AI Credentials screen to point to the new Connectors screen
• Ensure our API validation check uses the new keys stored as Connectors
• Switch to using wp_ai_client_prompt instead of using AI_Client directly
• Run all of our tests on trunk only for now as they'll fail on 6.9
• Update the JSON schema for the Review Notes Experiment to work with the Responses API

Use of AI Tools

All initial work was done by me with AI helping debug and fix failing tests

Testing Instructions

1. Install WP 7.0-beta3
2. Install the plugin from this branch, ensuring you're building assets (npm i && npm run build && composer i)
3. Verify you see a new Connectors setting under Tools
4. Install a Connector and add a valid API key
5. Ensure you don't get an error message on the AI Experiments settings page
6. Turn on one or more Experiments and ensure those still work

Note

Plugin Check is still failing but that's due to an upstream issue that should be resolved in their next release.

[codecov]

Codecov Report

❌ Patch coverage is 36.36364% with 28 lines in your changes missing coverage. Please review.
✅ Project coverage is 57.72%. Comparing base (9db302e) to head (19e1327).
⚠️ Report is 31 commits behind head on develop.

Files with missing lines	Patch %	Lines
includes/helpers.php	0.00%	13 Missing ⚠️
includes/Settings/Settings_Page.php	0.00%	4 Missing ⚠️
includes/bootstrap.php	0.00%	4 Missing ⚠️
...bilities/Excerpt_Generation/Excerpt_Generation.php	0.00%	1 Missing ⚠️
includes/Abilities/Image/Alt_Text_Generation.php	0.00%	1 Missing ⚠️
includes/Abilities/Image/Generate_Image.php	0.00%	1 Missing ⚠️
includes/Abilities/Image/Generate_Image_Prompt.php	0.00%	1 Missing ⚠️
includes/Abilities/Review_Notes/Review_Notes.php	93.33%	1 Missing ⚠️
includes/Abilities/Summarization/Summarization.php	0.00%	1 Missing ⚠️
...es/Abilities/Title_Generation/Title_Generation.php	0.00%	1 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##             develop     #275      +/-   ##
=============================================
+ Coverage      57.68%   57.72%   +0.03%     
  Complexity       567      567              
=============================================
  Files             35       36       +1     
  Lines           2933     2933              
=============================================
+ Hits            1692     1693       +1     
+ Misses          1241     1240       -1     

Flag	Coverage Δ
unit	57.72% <36.36%> (+0.03%)	⬆️

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[github-actions]

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

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[jeffpaul]

Looks good to me, but I defer to @felixarntz for any code review concerns (though also fine to merge in to continue with work building towards 7.0 and we can always come back to iterate in another PR if needed)

[raftaar1191]

Additional Fix: Resolves Fatal Error with WordPress 6.9+

This PR also resolves a critical fatal error that was occurring in v0.4.1 when the plugin was activated with WordPress 6.9+:

Fatal error: Call to undefined method WordPress\AiClient\Providers\DTO\ProviderMetadata::getAuthenticationMethod() 
in /wp-includes/connectors.php:164

Root Cause: The bundled php-ai-client v0.3.1 (via wp-ai-client ^0.2.0) was missing the getAuthenticationMethod() method that WordPress core's connectors.php was calling.

Resolution: By removing the bundled dependencies and moving to use WordPress core's AI Client, this PR eliminates the version conflict entirely.

Issue: #285
Impact: Critical - caused complete site failure for users on WP 6.9+ with v0.4.1

Great work on this refactor - it solves both the architectural goal AND a blocking compatibility issue! 🎉