Expiring report links and an integrity breakdown

What changed

• Shared candidate report links can now be set to expire, and you can revoke a link from the same dialog.
• The integrity notice on a candidate report expands into one row per signal, with a link to that moment in the replay.
• Technical and non-technical recruiters now use the same assessment builder. Each question's AI mode can be changed right on the Review and publish step, and each question can limit which models candidates may use.