integrate response feedback with langfuse

[miguelgrc]

Closes cern-sis/issues-inspire#993

Integrates the UI feedback elements with the langfuse user feedback tracing.

• Added also a comment button next to the existing thumbs up and thumbs down
• Feedback is linked to the langfuse trace of the response
• When clicking back and forth between thumbs up/down or adding a comment, the feedback is linked with the langfuse score_id for that trace, in order to prevent duplicate entries, and will instead do an upsert.
• When adding a comment with no rating selected, the thumbs up will be selected by default (it can be modified by the user afterwards)