Deprecate AI Search in favour for the contrib version
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## Summary
The AI Search module provided in the AI Core module should be deprecated in light of the AI Search module provided in contrib:
https://www.drupal.org/project/ai_search
We'll need a change record for this change.
## Problem
The AI Search module in contrib should be prioritized rather than the one provided by the AI Core module.
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## Proposed solution *(optional)*
Deprecate the AI Search module in the AI Core module, and refer to the contrib version instead, similar to the approach taken with the AI Translate module:
https://www.drupal.org/node/3570275
issue