Restore corrupted timestamps from the append-only log

When a bug overwrites an aggregate/derived field (e.g. last_contacted) with wrong values, do not just ship the fix and leave the bad data in place. The append-only event log that originally drives that field is your ground truth — for each affected record, find the latest event timestamp and write it back. Same shape works for any cached/denormalised field where the source-of-truth log exists. Bonus: when the user gives you names from memory to fix, treat the spellings as approximate (Kaita → Katia) and use the corruption fingerprint (in this case last_contacted set to the deploy date) to disambiguate, not the name alone.