Add "project.column.search" for querying workboard column information
Ref T12074. Provide a basic but functional v3 API endpoint for reading workboard column information.
There is no equivalent to this in the UI yet, although there may be some day (perhaps adjacent to T5024).
- Queried for all columns.
- Queried for columns on a particular board using projectPHIDs.
Reviewed By: chad
Maniphest Tasks: T12074
Differential Revision: https://secure.phabricator.com/D17157