phabricator: add a "phabstatus" show view
We add a "phabstatus" show view (called as "hg show phabstatus") which
renders a dag with underway revisions associated with a differential
revision and displays their status.
The revisions shown is a subset of that shown by "work" view, only
including revisions with known by Phabricator.
Differential Revision: https://phab.mercurial-scm.org/D7506
[tool.black]
line-length = 80
exclude = '''
build/
| wheelhouse/
| dist/
| packages/
| \.hg/
| \.mypy_cache/
| \.venv/
| mercurial/thirdparty/
| contrib/python-zstandard/
'''
skip-string-normalization = true
quiet = true