ui: added single line reasoning preview (#23601)

ui: added single line reasoning preview (#23601)

* webui: added single line reasoning preview.

* patch: reduce width slightly for the previewing section

* refactor: move formatter constants to the right file

* feat: reimplement reasoning preview with throttled dynamic per-line rendering

* chore: fix spacing

Co-authored-by: Aleksander Grygier <redacted>
* chore: refactor to requested changes

* refactor: grouped by capture pattern instead of block-level + inline

* ui: fax interrupt state only trigger for 1st reasoning message

* chore: make reasoning preview respects showThoughtInProgress setting

* chore; newline at EOF

Co-authored-by: Aleksander Grygier <redacted>
* fix: thread rawContent so collapsible content can handle compute preview

* patch: showThoughtInProgress accidentally blocks rawContent being passed

* chore: fix lint

* chore: change smoke test

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Co-authored-by: Aleksander Grygier <redacted>