Merge master: the downloadable builds

Three files disagreed. The test workflow gained a job on either side, so
both stay: the Mac now parses the release and packaging scripts as well,
and Windows keeps its own job below.

`restart` and `launch_gui` both start Dikte again, and master moved that
argv into `ipc.launcher()` because a packaged build has no `__main__.py`
to name. Windows still cannot use execv there, so the detached start it
needs now takes what the launcher hands it rather than spelling the
interpreter and the script itself.

The test counts in CONTRIBUTING are the suite as it stands after the
merge: 1104 of 1147 run anywhere, and the 43 left are the Linux ones.

CONTRIBUTING.md

@@ -70,7 +70,7 @@ there can tell that apart from an empty device list, which only means the tool
 that lists them is not installed.
 
 The tests are split along the same line, and almost none of them are skipped.
-1067 of the 1110 run on any machine, including every line of the Wayland, X11,
+1104 of the 1147 run on any machine, including every line of the Wayland, X11,
 macOS and Windows backends: the programs are faked at `shutil.which`, the
 frameworks and system libraries at the one function that loads them
 (`paste._win_api`, `hotkey._win_input`). A test class says which system it is