vere: require authentication for webslogs
vere: require authentication for webslogs

By scrying into Eyre to see if the cookie included in the request makes
it an authenticated request.

Depends on #3628.

urbit/urbit,urbit/urbit,urbit/urbit,urbit/urbit,ngzax/urbit,ngzax/urbit,urbit/urbit,ngzax/urbit,urbit/urbit,ngzax/urbit,ngzax/urbit,urbit/urbit,ngzax/urbit,ngzax/urbit