fix: text content is not indexed to meilisearch for some providers

[sarisia]

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Summary

Fix llm response text content is not indexed to meilisearch for some providers (confirmed with bedrock)

Change Type

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• Bug fix (non-breaking change which fixes an issue)

Testing

Please describe your test process and include instructions so that we can reproduce your test. If there are any important variables for your testing configuration, list them here.

Test Configuration:

Checklist

• My code adheres to this project's style guidelines
• I have performed a self-review of my own code
• My changes do not introduce new warnings
• Local unit tests pass with my changes