Fix Gaphor Launching Fails in macOS

[amolenaar]

What is the current behavior?

What I try to solve is why Gaphor will not open a model via finder (e.g. double-click on the desktop).

What is the new behavior?

Gaphor is started via a binary, instead of a shell script. This ought to fix the loading issue, but there's more going on.

As a plus I get logging in the Console.app at least. That alone makes the change worth it.

Does this PR introduce a breaking change?

• Yes
• No

Other information

I took some stuff from py2app. We may want to start using that as our starting point for packaging on macOS at some point.

When I click on a model, I get the following dialog (served from Gaphor by looking at the menu bar):

Edit: Solved! The file-open events from macOS do not reach the application. I had to add gtk-mac-integration to handle the file-open event, as well as the quit event from the dock icon.

[sourcery-ai]

Sourcery Code Quality Report (beta)

❌  Merging this PR will decrease code quality in the affected files by 0.02 out of 10.

Quality metrics	Before	After	Change
Complexity	1.41	1.52	0.11 🔴
Method Length	36.68	37.38	0.70 🔴
Quality	8.98	8.96	-0.02 🔴

Other metrics	Before	After	Change
Lines	322	329	7

Changed files	Quality Before	Quality After	Quality Change
gaphor/application.py	9.22	9.21	-0.01 🔴
gaphor/ui/init.py	8.68	8.63	-0.05 🔴

Here are some functions in these files that still need a tune-up:

File	Function	Complexity	Length	Overall	Recommendation
gaphor/ui/init.py	run	12	154.91	5.57	Split out functionality

Please see our documentation here for details on how these metrics are calculated.

We are actively working on this report - lots more documentation and extra metrics to come!

Let us know what you think of it by mentioning @sourcery-ai in a comment.