Use ApplicationSearch in Slowvote

Summary: Ref T2625. Ref T603. Make the vote list policy-aware, mobile-friendly, and use ApplicationSearch.

Test Plan: {F50022}

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T603, T2625

Differential Revision: https://secure.phabricator.com/D6445