R1:320be1a1b8d4

Modernize user activity logs (ApplicationSearch, policies)

Summary:
Ref T4398. Ref T4842. I want to let users review their own account activity, partly as a general security measure and partly to make some of the multi-factor stuff easier to build and debug.

To support this, implement modern policies and application search.

I also removed the "old" and "new" columns from this output, since they had limited utility and revealed email addresses to administrators for some actions. We don't let…