Port "arc weld" and "arc anoid" to Toolsets workflows, plus minor fixes

Summary: Ref T13490. Update the "weld" workflow and the "anoid" workflow. Incorporates D20938.

Test Plan: Ran "arc weld". Ran "arc anoid".

Maniphest Tasks: T13490

Differential Revision: https://secure.phabricator.com/D21001