R1:d118800d3794

Support Spaces in Maniphest

Summary:
Ref T8493. Tricks:

- "Create Similar Task" and "Create Subtask" should copy the parent's Space.
- Normal list view + workboard card view.

Test Plan:
- Created a task, edited space, etc.
- Viewed tasks with different users.
- Created a "Similar Task" (saw proper Space).
- Created a subtask (saw proper Space).
- Viewed workboard.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T8493

Differential Revision: https…