[Redesign] More header touch ups

Summary: Ref T8099, We moved to phui-header-header for targeting the internal title in the header vs. the entire header-view. There were some pieces that didn't get converted over. Also resolved some dashboard feed issues.

Test Plan: Test lots of dashboards.

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Maniphest Tasks: T8099

Differential Revision: https://secure.phabricator.com/D13086