R1:d90496a7192d

Conpherence - make timestamps in durable column link to full message in conpherence

Summary: Ref T7757. This diff made me realize that `PhabricatorTransactionView` is only used in Conpherence, as well as that `ConpherenceTransactionView` is more like a rendering class with a few static methods. Going to take a diff after this to clean all that up.

Test Plan: opened up durable column, clicked on timestamp, voila!

Reviewers: chad, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley…