Prepare a replacement for Controller->renderHandlesForPHIDs()

Summary:
Ref T7689. This gives HandleLists renderList() and renderHandle() methods, which return views that can perform just-in-time data fetching and generally look and feel like other rendering code, instead of being odd pseudo-functional methods on Controller.

Also converts callsites on the Maniphest detail page to use these methods.

Next changes will wipe out more of the callsites.

Test Plan:

• Viewed Maniphest detail page with many relevant handles.
• Created a new subtask.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T7689

Differential Revision: https://secure.phabricator.com/D12205