Fixes: #18943
Follow-up pr: #19001
## Summary:
- Timeline activity shows file upload history, but deleted files had no
signed URL and were still rendered as clickable — clicking did nothing
- grab the fileId from properties.diff.after, look it up in the current
record's files field: if present, use live signed URL; if absent, mark
as deleted
- Deleted file chips show line-through label, not-allowed cursor, and
"File no longer exists" tooltip on hover
https://github.com/user-attachments/assets/5df6a675-0003-4fd1-ad57-a07e4338923f
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Co-authored-by: Etienne <45695613+etiennejouan@users.noreply.github.com>
BugIsGod
bcca5d0002