R1:dec03cf07683

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…