v2t: add v2t to client/branded

[dadlerj]

Context:

https://docs.google.com/document/d/17REfT9UCu3nANKEIRBUw3HiNpiTYhg5gikMclqMuWaU/edit

Test plan

sg start visit page check if events appear in event_logs table locally

[dadlerj]

This PR is relatively low risk, but it hits a lot of different minor components throughout the app, so testing is difficult. I can make a post about watching for dotcom errors after merging.